M42club.com - Home of the BMW E30/E36 318i/iS
DISCUSSION => Electrical => Topic started by: bmwman91 on April 21, 2006, 11:36:07 PM
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Well, after some fiddling with the system's transfer function, the car now runs like a champ. The 1st set of conversion values I used had a little discrepency (the resistor I used to mimic the ambient air temp sensor told the ECU it was 21.4C, while the air flow was converted at 11.6C...oops). It caused the car to think there was 3-4% less air going in that there actually was...and a 3% lean condition is a LOT. That would kick a target AFR of 15 to ~15.5. Oops...
Anyway, I fixed the mistake and BAM it runs great. Just by looking at the instantaneous MPG gauge I can tell all is well...behaves the same as when the AFM was in there...the Motronic thinks the AFM is in there, which was the goal.
Now, who cares about the above stuff, right? You want:
Results:
- Idles a LOT better...none of that unsteady nonsense...and the coming-off-throttle stumble is all gone.
- The car is a LOT louder at WOT, but that is because I have an open-element filter on there at the moment.
- The midrange power seems a little better, as does the high. There is a weird power-deficit at 4-5000RPM. That I attribute to the air box being gone. Removing it changes the induction track harmonics. I guess it did so in a way that between 4 & 5kRPM the pressure waves cancel a little more. I am still making an adapter to fit the air box, but I will also look into adding a Helmholtz resonator or velocity stack at the intake entrance to help this.
- Mileage should be better in one respect. When you floor it with an AFM, the door has some inertia, and flies open a little past where it should be. The Motronic sees this, and will momentarily inject too much fuel while the transient effects of the trap-door system are still significant. Once it reaches its 'steady state' its fine...but those momentary over-injections add up I would guess (well, if you like to floor it like I do, esp on the HWY). This also kills the catalyst faster, so good riddance.
I will report again after a few days. I only got about 30 minutes of test time today, but seeing how it does around town will be a good test. Thank God I'm done...my end-of-semester just got easier!
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awsome!!!
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dude, that is so sweet man. get some 0-60 and 1/4mi times stat! congradulations on the success
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I would get it run on a dyno to see what the air/fuel does in general and especially where the power deficet is. I doubt its because of the harmonics
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Haha Nick has discovered me...jk.
Yeah, I have to figure out what the deal with the 4kRPM is. Honestly, I think it is a change in the induction system harmonics. The deficit is there under WOT conditions. In WOT, the Motronic goes into Open-Loop mode, ignoring the AFM input. Being that the M42 is HIGHLY tuned from the factory, something like removing the air box could easily cause significant changes in the power curve IMO.
Now, perhaps I am just noticing an improvement in the rest of the power curve, with less pronounced results in the 4k-5k range. It is speculation at this point. When I have a chance/$$$ I will dyno it and see exactly what the difference is. I have an LC-1 WBO2, so I can monitor the AFR. Hopefully within the next few days I will be able to get some REAL analysis back to you all. Unfortunately I am very very busy working out my career plans. I am trying to nail down a job at either NUMMI or Cisco Systems, so that is priority #1 right now.
PS
Pleas forgive any spelling errors. I am drunk as shit right now...in celebration of my MAF success. Going to work tomorrow at 9AM is gonna suck royally!
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Haha Nick has discovered me...jk.
Yeah, I have to figure out what the deal with the 4kRPM is. Honestly, I think it is a change in the induction system harmonics. The deficit is there under WOT conditions. In WOT, the Motronic goes into Open-Loop mode, ignoring the AFM input. Being that the M42 is HIGHLY tuned from the factory, something like removing the air box could easily cause significant changes in the power curve IMO.
Now, perhaps I am just noticing an improvement in the rest of the power curve, with less pronounced results in the 4k-5k range. It is speculation at this point. When I have a chance/$$$ I will dyno it and see exactly what the difference is. I have an LC-1 WBO2, so I can monitor the AFR. Hopefully within the next few days I will be able to get some REAL analysis back to you all. Unfortunately I am very very busy working out my career plans. I am trying to nail down a job at either NUMMI or Cisco Systems, so that is priority #1 right now.
PS
Pleas forgive any spelling errors. I am drunk as shit right now...in celebration of my MAF success. Going to work tomorrow at 9AM is gonna suck royally!
good work! you really think the m42 is highly tuned out of the factory? I'd say its pretty conservatively mapped, or at least ours in th UK are.
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Congratulations!
And I wish you the best of luck and success with getting the new job.
Chris
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Now that you have succeded now time to produce them and sell them to us. I have been working with an smt6 but I would love a plug and play set up instead.
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good work! you really think the m42 is highly tuned out of the factory? I'd say its pretty conservatively mapped, or at least ours in th UK are.
Well, I was referring more to the construction of the engine being well-done. I agree, the original software was quite conservative.
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yeah man, here's a job idea: mass produce these bad boys! i know probably a good half of members here would buy, and who knows how many else would. just a thought.
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I am working on getting a product together that I would feel confident selling. Right now it is a working prototype, and I am designing a PCB to be made, as well as selecting the smallest possible housing and whatnot.
Here is the hard part: Fitment.
The electronics are not too big a deal, and I could have a converter made & ready to go within a month or 2. Now, if I had to make adapters & stuff so it fit reall really easy, that will be a while. Right now I have it fitting in with a $4 reducer from AutoZone and a 35 cent pipe fitting from Home Depot. That is for the MAF-to-Air Boot side anyway. Making it fit the air box is another story. I have a big open-element K&N on there right now, which works. I could also try to make a heat shield so an open element filter could be used instead, but that is still $$$ & time.
So, how do all the DIY'ers here feel about me selling them the converter box and necessary connectors that have to be spliced in, but it is up to you to get the MAF (easily sourcable at wreckers, or refurb'ed at kragen for like $60) fittings and filter (and make a heat shield yourself)? I am still looking into the air box fitting...I just need a really short silicone reducer. The only other part needed will be the circular-to-square adapter found on M10s' & M20s' AFM's.
So, what do people here want? I will do my best to figure out the adapters...my current ones WORK, but are not as nice looking as I would like.
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just give me the converter ish
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^ what he said.
what MAF were you using again?
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So, how do all the DIY'ers here feel about me selling them the converter box and necessary connectors that have to be spliced in, but it is up to you to get the MAF (easily sourcable at wreckers, or refurb'ed at kragen for like $60) fittings and filter (and make a heat shield yourself)? I am still looking into the air box fitting...I just need a really short silicone reducer. The only other part needed will be the circular-to-square adapter found on M10s' & M20s' AFM's.
So, what do people here want? I will do my best to figure out the adapters...my current ones WORK, but are not as nice looking as I would like.
I have no problem with that.
Kind of leaves it open for you to experiment with the air cleaner side, and decide what is best for you without paying for something you do not want.
The big question is what would we be looking at for your kit?
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I will try to get you all some pricing info within the week. I just finished drawing up the PCB layout. So, once I have all my costs nailed down and my partner & I talk it over we will let you know.
And it makes my life a lot easier at this point hearing that you just want the magic box. More to come.....
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doesnt the stock m42 have a dip in that range?
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I have monitored the AFM and at 4-5k there is turbulence in the output voltage,
Itīs very noticeable, I would guess itīs there for because of intake design,
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I have monitored the AFM and at 4-5k there is turbulence in the output voltage,
Itīs very noticeable, I would guess itīs there for because of intake design,
Well, good to know. Perhaps the problem is more pronounced with an open-element filter than with the air box (all those little redcers and whatnot were in there for reasons afterall, and not just noise reduction).
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yeah man, we're pretty tech savvy, so we could do w/ the wiring and some diagrams or whatever. just give us specs on the maf and other nessecary hardware and we can all fab our own kinda custom system. i have already done that anyways losing the airbox and stock intake hose.
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Alrighty. Well I will finish up getting a BOM together. All I really need still are some weatherproof connectors. Anyone know a good source?
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Alrighty. Well I will finish up getting a BOM together. All I really need still are some weatherproof connectors. Anyone know a good source?
Any marine supply places. They are more expensive, but well worth it IMHO. Try WestMarine or Boater's World. They even sell the type that snap together and then have shrink wrap sheathing built in. I usually just get the normal waterproof ones though.
This crimps are much higher quality too!
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I have no problem hooking up the converter and connecting a maf to some kind of air filter. I assume the converter is calibrated to work with a specific Ford Maf with a known flow rate, what Ford maf is this since I have one off of an escort working on my car now I was just wondering if I need to find another one specific for your converter. By the way congrats on the success you would be an asset to whom ever employees you.
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well... hopefully this MAF thing will take off, and he won't need someone to employ him!
(CONGRATS MAN!)
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Thanks guys. Hehe, the plan is to work for someone else for a while after graduation to pay off my $70k in student loans, then see about getting my own business rolling. Of course, I will have my weekend projects that will be products I plan to sell!
The MAF is the 55mm-throughway one found on the 89-94 Mustang GT's, and 91-93 3.8L Taurus I BELIEVE. The PN you are looking for is F1ZF-12B579-AA. Here are some pics of it.
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where did you get that MAF? I'm having trouble finding it, even using the part number. are you sure that is right?
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what's the update man? howd your project turn out?
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I've read that the cone filters sans airbox does not work well with an MAF because of the way the air flows through them. Actually, I've read that cone filters do not work well at all and cause a loss in power (see the May GRM article I posted where they dynoed it at -5hp). I'd be curious to see how your MAF performs with a stock air box & panel filter; I bet it would be a significant improvement.
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Hey sorry about the long delay in response. School has been killing my time.
Well, I got 2nd place with my senior project, so I would say it went well. The car runs well still. I actually swapped the AFM back on yesterday, and wow, the MAF did make a pretty big difference. I still notice a small dip in power between 4200 & 4500RPM, just not as pronouncd.
As for the turbulence issue...I flow tested the MAF with the cone filter strapped onto it and it gave very steady readings. I would have expected there to be some turbulence issues, but there were none. Now, in the case of this very large MAF, if it was connected to the stock airbox I would imagine that there would be problems. From testing, I saw that having any sort of expansion in tube diameter (which there would DEFINITELY be coming from the air box to the MAF) immediately before the MAF caused very unstable readings. The same was true to some extent for reductions in the tube. I am working on a heat shield for this in the next few weeks for my car, but for now the converter will be sold as-is.
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congradulations on the success! I use a cone filter anyways that I have routed w/ a strait pipe and a 90deg. bend so that the filter is actually right behind the LEFT brake duct if you are looking at the FRONT of the car. I cut a hole out of the plastic dirt guard underneath the engine on the side so that the filter always has access to fresh air, even at idle. I'll try to get some pics of this. it works really well and i don't feel like i have any power loss even in stop and go traffic b/c of the heat shield and hole.
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Awesome!
can't wait.
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congradulations on the success! I use a cone filter anyways that I have routed w/ a strait pipe and a 90deg. bend so that the filter is actually right behind the LEFT brake duct if you are looking at the FRONT of the car. I cut a hole out of the plastic dirt guard underneath the engine on the side so that the filter always has access to fresh air, even at idle. I'll try to get some pics of this. it works really well and i don't feel like i have any power loss even in stop and go traffic b/c of the heat shield and hole.
I'd love to see photos of this too!
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I don't know how I missed this thread. Congrats on getting the MAF to work!
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where did ya post the DIY. i'm glad someone figured this out..i gave up after 5 mins of tinkering with my multimeter. why would the resistance go up and then back to ~starting resistance. this is cool though.
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Hehe, well, the DIY will be for how to install a converter I am eventually going to be selling. My partner & I are finishing up a few things before releasing the product.
Regarding the VAM question: when you open the throttle (the effect is most prononced when you floor it fast/hard) the air flow into the engine increases suddenly. The 'trap door' opens further with this increase in flow (reducing the resistance). Now, the door has some mass to it, and prettymuch no damping, so it flies open past where it should be for the EXACT air flow measurement, just momentarily (not something you would be able to see on a multimeter, we are talking fractions of a second here). It is just an inertial effect of having a relatively massive object moving around as part of the measurement device (massive relative to the air flowing).
Now, even with a MAF you have the same effect due to the air acting as a spring-mass-damper system, but the effect travels at the speed of sound, and due to its very low density, the inertial effects within the flowing air are inconsequential at their most (within the primary intake track where the MAF & throttle plate are being considered...these effects define prettymuch everything about an engine's performance AFTER the throttle plate and within the exhaust manifold).
Aah, the joys of tinkering with induction systems. Ignorance is bliss...it all seemed so simple before I had 4 years of engineering class (only 1 more to go, YAY!).
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Before I was into these cars I did a lot of work with DSM's (eclipse/talon turbo) and they had a similar device made for em. They had a translator box that took a gm hotwire mas air flow meter output and outputed to the ecu what it needed.
There is tons of research about this topic, I believe there is a yahoogroup on the topic as well. I just looked at the site of the guy who created it and apprently he has developed an upgrade that uses a gm map sensor and converts to a speed density design.
Well here is his site http://www.fullthrottlespeed.com/items~Cc~REGTRANS~iTpStatus~0~Tp~~Bc~.htm
Here is the yahoogroup http://autos.groups.yahoo.com/group/dsmtranslator/
He also has a messageboard, I also just noticed he added support for the mkiii supra, that uses a flapper style meter similar to ours.
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Very interesting...
I toyed with the idea (well, still am toying) of going to speed-density. I guess now that I am out of college & have free evenings/weekends I could start doing some data gathering. Benefit-wise though, speed-density offers a couple milliseconds better throttle response than MAF, a LOT more required tuning (on the developer end anyway), and at least as much custom plumbing.
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any news on this mr bmwman?!
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Heh, yes actually.
I am ordering the parts for the 8 half-ready converters this week. I still want to find a smaller MAF though. Well, I do not really care too much, but I don't want to get stuck with customers crying because the big Ford one is hard to fit and will not look perfect when in place. You'd think that saying "all install work & fitment is up to YOU the buyer, and the MAF is not something you just pop right in" would scare off the ones who can't turn a screwdriver, but i do not want to have to deal with refunds.
So, if people here want a converter as it stands NOW, I'll sell one no prob, but the 55mm Ford Mustang MAF is not gonna look like Conforti designed the setup or anything. That's why I want a smaller one...I take pride in what I do and do not wanna sell a kit where things look shabby when all done. It does not HAVE to look shabby, it just depends on how much work the buyer puts into fitting the MAF.
BTW: The kit includes the Converter Box, wires & connectors, and instructions. The MAF is for the buyer to find.
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Although I'm megasquirted so its not for me really, i'm still really intrigued at this! have you 'mapped' the new setup with your wideband etc? be cool to see a really straightforward conversion like this, i think its a great idea!
btw once you're ready, if you'd like me to see if anyone in the UK is interested, let me know, as I reckon there'd be quite a bit of interest. would have to be a complete product with the MAF etc though i reckon as the MAF you've picked is probably difficult to find over here.
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yeah is the engine running lean or rich? with what injectors? is there still a "hole" in the powerband?
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There is NO mapping necessary on the user end. It is NOT tunable, it is just 'plug it in and drive.' Aside from the cost of a Split Second converter, the other big turnoff to MOST people (and a smart product developer will make stuff for MOST people) is that you have to tune it yourself...and there is risk involded in that, as well as even more cost if you want to tune for any additional power (dyno time).
The hole in the powerband...
Well, it is there with my AFM on the car as well, just less pronounced. Take a look at the attached Excel file. There is a nice big dip in the torque curve from 3900 - 4300RPM, causing a reduction in the RATE of increase of power. If I could get a like 12th or 16th order polynomial best-fit line on there, and take its derivitive, I could see just how much less the power curve's slope is than everywhere else on the plot. Also, it may not be the lowest slope on the power curve, but one can feel the effec in a more pronounced fashion as the low-slope part sits right between two of the steepest parts of the power curve. It is like putting your hand into 35C water...after having it sit in some 3C water...the warm water will FEEL a LOT hotter than it actually is. Anyway, the chart i added on the end is zoomed in to the dip. Let's hear some of you guys' analysis of this.
(Dyno...from my first 318IS, running AFM/JC Chip/some exhaust stuff/pointless intake)
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Bump to the top because I've almost stalled my car twice this week because of the retarded flapper door AFM.
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Lol I will sell you my spare AFM? A redesign is gonna be getting done on the current converter & a new (better fitting) sensor used, but that will be a couple months since my real job is kicking my ass.
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Haha no I don't need a new one, I just need to not give it so much gas off idle. Most other times it runs OK, but I do have some sort of vacuum leak. What I really need is a new lower front bumper (where the fogs/brake vents go), if you have any of those laying around, I'll buy it off ya.
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HAHA... Deutschbag... I tried to get that name on VWVortex but the admins vetoed it and refused to activate the account. I needed a smartass screen name and that's how I ended up with "EuroNation", a joke 98% of the people never understand... and it eventually became my business name.
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so when can we expect these?
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ok so you've gotten help a guy out here..... i understand the general workings of a motor, but before this bimmer i was mainly a fix whats broke kinda guy....... when we starting geting into the fuel injection system, or any of the computer, i just got confused and paid someone to do it....
so i'm cruisin in my 95 318, i'm pretty sure i'm running on an AFM, why would i want to swtich to an MAF?
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Why a MAF? :
- Better throttle response (esp. off-idle and below 3000RPM)
- Nearly eliminates the stumbly idle
- No more bogging-idle when coming off-throttle
- A little power gain (no numbers yet...will be once it is complete)
- Marginally better fuel economy / catalyst lasts longer*
I guess I owe an update.
I am like 70% done with Version 2.0 of this. I am using a Bosch sensor that wil fit the boot and air-box with $7 in rubber/silicone fittings and is better sized for this application. I have all the translation maps done and programmed into the magic box, but there is a similar issue to the one V1.0 had...but it occurs between 2000 & 3000RPM and is a lot worse (to the point that the ECU cuts the injectors). Now, the WBO2 sensor in my car crapped out on me, so that could be contributing to the problem. Once my replacement arrives (hopefully tomorrow), I will see what exactly is going on in there. The problem only persists at near full-throttle when below 3000RPM. Above there, if you floor it, it GOES. The car feels so peppy, I just hope gas never hits $5/gal because I will have to cut back on groceries to buy gas (Ramen is cheap, right?)!
The idle was smoother once again, and power came on stronger and more smoothly in the upper range. There is NO hesitation between 4000 & 4500RPM any more...it is smoother than it was with the AFM. I am really excited about this, and I am sure there are many who are more so than I. Just bear with me on this, I do not want to sell anything until I am confident that I will be dispensing a quality product; a product that I would be happy with if I purchased (and I am one of those customers you hate...I expect perfection).
*When you pounce the throttle, the flapper-door opens rapidly, and overshoots the proper position (it has mass, and carries momentum). For that brief moment the ECU is told there is a LOT more air flowing than there really is, and it will over-inject fuel for that moment. Extremely rich bursts like that foul spark plugs, build carbon deposits and reduce catalyst life.
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so your going to be selling what with all this? programed MAF ready for bolt in? or are we going to be programing them ourselves? I have no problem (if your willing and all the problems are solved) buying a MAF for the conversion, shipping it to you, have you do the diddly on it and sending it back? or is it something i would have to do while its in my vehicle....cause i'm not so good when it comes to the electronics stuff.....I also wonder the differences between my OBD1 serpentine setup and yours when it comes to such a sensor....would be interesting
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hi guy put me on the list i want to know how that will cost an probably comand one i am very iterest because a reonditioned one its 800$ cad
so pm me please
marc-andré:)
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Why did you use a Ford MAF?
I used a 328i MAF on my conversion, works beautifully!
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*When you pounce the throttle, the flapper-door opens rapidly, and overshoots the proper position (it has mass, and carries momentum). For that brief moment the ECU is told there is a LOT more air flowing than there really is, and it will over-inject fuel for that moment. Extremely rich bursts like that foul spark plugs, build carbon deposits and reduce catalyst life.
Datalogs show that A/F hits the low 10:1 range when this happens. Not a good thing.
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I used a Ford one because of its low price and ready availability at wreckers. I was having a hard time locating a smaller Bosch one (that does NOT undergo the burnoff cycle) for a price that was reasonable. Nobody is going to want to have to sepnd $200 on the converter and then $300 on a MAF.
Thanks to Euro Nation here, he tipped me off to a unit used on later model VW's. I want to build calibration curves for a BUNCH of sensors though, so the buyer can use virtually whatever sensor they want/is readily available to them. Anyone have extra MAF's for me to borrow lol? I would love to map a M52 sensor.
This thing is intended to be plug-n-play. No programming needed by anyone. You snip your AFM harness, and substiture the MAF connector on the end, hook up to switched 12V power, secure the magic translator box and go. I will provide all connectors (will probably be simple bullet connectors since I do not want to make people go buy $20-$100 crimpers for fancy connectors). I will also ship extras so you can put them on the AFM connectyor should you ever need to go back to it. I would LIKE to ship these with nice weatherproof ones, but you need special tools to properly crimp the wires into the pins. If someone knows of a good way to go weatherproof without expensive tooling, let me know. it is in everyone'e best interest.
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OK. Time for another idiot question. What is the downside to doing this, other than the price? What are the trade offs? This almost sounds too good to be true.
I'll admit I was a little turned off earlier when you were using the Ford Maf, mainly because of the need to go with a cone air filter/homemade intake. now that it looks like you can keep the airbox, I'm becoming seriously interested. i.e. put me down on your list of waiting customers!
brian
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paypal standing by...
Chris
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Downsides...ummmm maybe there is a little more engine noise since there is no flapper door in there to mufle it?
You will also likely get ass mileage after this as you will want to floor it everywhere. I am not kidding.
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well i am DEF interested in being a pioneer in the buying of ur project when you get some kits made up. just keep us updated and im sure you will be making mad money and getting mad props from more than a few M42 owners. props man, good work
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Downsides...ummmm maybe there is a little more engine noise since there is no flapper door in there to mufle it?
You will also likely get ass mileage after this as you will want to floor it everywhere. I am not kidding.
I was getting an extra 50km on one tank after doing my MAF conversion.
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I was getting an extra 50km on one tank after doing my MAF conversion.
What converter you use for your maf conversion?
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I was getting an extra 50km on one tank after doing my MAF conversion.
Well, I guess the MAF is just the gift that keeps on giving!
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Now that I have a nice new Bosch LSU4.2 wide-band sensor in there I should try out the MAF conversion to see if the problems disappeared. The old one was shot to hell, and the car runs 10 times better now. If all is well, then that could cut a couple weeks off of redevelopment time!
I ordered up a round of PIC MCU's and will be building a reeeally basic datalogger to take RPM, air flow and EGO readings. So, if the thing still acts silly at WOT below 3000RPM I will have to build & program a little DAQ setup to see what is going on. Cross your fingers I don't!
PS
Anyone wanna write some simple C or BASIC code to take some serial data in from an RS232 port? It will be 2 8-bit numbers and a 16-bit one. Just have to be stored in a 3-column, tab-delimited text file, and that much I can probably do myself after refreshing stuff I learned 3 years ago.
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What converter you use for your maf conversion?
Dastek piggyback Unichip.
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In regards to the stutter this might help,
This was on another forum, sourced from a manual, dealing with a different bmw with a afm. They were not going to maf, just saying its the same basic setup and someone was having a stutter about like yours. And here was one of the possible causes..
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"The shut down happens if the air volume sensor registers an air volume that is higher than permitted for current RPM and load, for more than 1.5 seconds. The limit is at 15% above the volume at full throttle. When injection is turned off, the compression process collapses immediately. Injection is resumed when the air volume sensor registers a pre-determined value that is below the full throttle amount. This new value is maintained for 4 minutes as a cut-off value forthe injection unit.Engine performance is slightly reduced during this time. After 4 minutes,the original value is restored."
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So possibly, if this bmw works like the other, by 3k rpm, with the new maf, the cpu reads a higher air volume than is permitted for the RPM. This could mean your parameters are set too high in the 1k-3800k RPMs due to how much more free flowing the maf is (especially around idle), the (voltage?) reading might need to be lessened to look weaker so it doesnt trip this air/rpm ratio.
If there was a way to get the car to say 4500RPM before 1.5 second of turning the car on, in neutral, you could test this but 1.5 seconds is pretty short. If it holds the value for 4 min, probably wait 5 min before tries...
Ive been watching this thread for a while and really want to see it happen. Good luck with it, hope this helps..
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ha ha ha and the Gizmo has arrived....
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Hi guys,
I'm new to this club and thread.
I've been working on my own MAF conversion while keeping track of this thread. For the past 3 month, I've been trying to use a 320i and a Mercedes Pierburg MAF. (BMWMAN - FYI - the Pierburg MAF used in the Mercedes Vito diesel van is only about $50 brand new!).
I've blown the 320 MAF (i think!) while testing cause i can't get any voltage output from it. With the Pierburg MAF, I've hook up an APEXI SAFC II fuel converter to try convert the values to what the ECU expects. I know I need to dyno tune to a wide band O2 sensor to get it right. But i haven't even reach that stage!
Idle is horribly unstable. It goes cyclicly up to about 1500+ and down 200+ and then finally dies. When i correct the mixture up to 50% less fuel (i understand that the voltage output from the MAF is much higher than the AFM) i get pretty stable idle but the engine seems to cut when i gaz it.
I'm close to giving up so unless someone has an idea, i've got my paypal ready for BMWman's product!
BMWMAn - I would probably need you to ship the MAF together with your converter. I'm from Singapore and there aint no Mustangs or tauruses here!....or maybe you can callibrate one for the Europe/Asia market using the Pierburg MAF. The Vito van is real popular here and Europe and the MAF is dirt cheap!
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Would a VW Golf 4 1.9TDI MAF work? I've got one lying around catching dust all day. :D
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I have actually switched to a VW MAF for the newer version. It fits a lot better and is cheap. Still debugging the weird behavior, but it is looking more and more like it is related to being atached to the air box. It migth not be possible to work with it, at least with this sensor.
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Actually, the VW MAF (by Bosch) and the Mercedes MAF(by Pierburg) is similar and interchangeable. The housing may be different but the MAF inserts are the same. My Pierburg MAF was actually "borrowed" from my VW Transporter TDi (Eurovan in US i think).
It was supposed to be running the Bosch MAF but the Pierburg replacement was supposed to be better and cheaper. Not sure if these new generation of hot film MAFs with digital output (i think) are the source of our unstable idle.
I don't think the VW 1.9TDi MAFs will be too different from it.
Anyway, Bmwman....when can we expect your first production models?
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Haha, I wish I could say. I have been saying "a couple months" for the past 6. I am just having a bear of a time finding the free time and resources whilst still trying to maintain a relatively normal social life, a GF and work. Aaah, life.
The funny thing is, I will probably have a datalogger coming out of this as well as I have had to make one to diagnose some issues. It is a little 3-parameter one I am working on, but it can very easily become 10+ after the MAF is done. Friggin sub-projects to the main one........
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bmwman you always got the best projects. i bet this conversion, when finished along with the COP conversion would make for great throttle response and all out engine efficiency.
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Hi all,
Proud to announce that with BMWman's tips, i've finally managed to make my conversion work!!!
I think the root of the problem was the Pierburg MAF. Since i blown the 320 MAF, i was hesistant of buying another one and therefore was trying to use my VW Eurovan MAF. I think the signals from this diesel MAF is just too different from what the ECU expects.
Since BMWman's product is not near production, i thought what-the-hell lets just grab another MAF and start tinkering again. I sourced for a 325i MAF, short the temp-sensor (on the AFM harness) with a 1.5kohm resistor to ground and spend a couple of hours tuning the APEXI SAFC2 to send the right signals to the ECU.
Finally managed to get stable idle and the engine revvs smoothly to 3500rpm. I'm not revving beyond that till i do a full dyno tuning with a wideband. I've been driving the car around for a few days already and everything seems to work fine. My butt dyno already says it's quicker and built up revvs quickly! I've ordered a chip from a German tuning company and when that arrives in a couple of days, i'll do the dyno.
Strangely, my wierd problem of bogging after a warm start dissapeared together with the AFM! I wrote on another post that my car is fine starting from cold but when i restart it when warm, it will idle erratically and stumble for the first 1 or 2 minutes. It works beautifully after this 1-2mins but the whole problem will start again if i switch off and restart!
Now - i don't have this problem anymore!....anybody have a clue what may have been the problem?!
Many thanxs to BMWman's for the tips!.....FYI - i've left the GREY/BLACK wire on the AFM harness disconnected. Seems to work pretty well without that mysterios wire - whatever its for!
PS - Does anybody know what the GREY/BLACK wire in the AFM harness is for and if its ok to leave it disconnected?
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I BELIEVE that wire is the LLCO adjustment, and was only used on non-catalyst/non-EGO sensor cars. And congrats on getting it to work with the Apexi unit, good luck at the dyno. I am interested to see what numbers you put down.
Once my e-bay oscilloscope arrives thsi week, I think I can FINALLY finish up the new converter and wash my hands of the development stage for this! I am sooo tired of having this looming over my head...and I need tires, brakes, a couple pints of OEM paint for some refinishing and to make my 6-month insurance payment...I need to sell a few of these lol!
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ready to buy let us know!!
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werd. If i coud get one of these and a COP bracket in the first couple weeks of december that would be awsome
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Actually,
My car do have an O2 sensor and there is a dummy cat converter as well (came with the car when i bought it)
What does a "LLCO" sensor do? Is it ok to leave it disconnected? My car has been running fine without. I'll probably drop by a specialist for a diagnostic sometime next week.
But....i'm really not sure what's supposed to be in my car anymore cause it was originally an M40 engined E36 that has been transplanted with a 1995 m42 engine!
i'll keep u guys posted on the dyno results.
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What country are you in? That makes a difference in the ECU's programming. If it has a 1995 M42 in it, then chances are the ECU ignores any input from the LLCO pin as by then I believe they were all running EGO sensors.
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UPDATE:
So...I got all the code worked out for the converter. It has 4x the resolution of the last one, and does 1000 conversions per second (previous one was about the same). The O-Scope came yesterday...and not a moment too soon. After a few hours of debugging my code and figuring out which lines were messing things up, things finally worked out and all input/output combinations checked out on the 'scope.
So, now I am jsut waiting on my shipment of the remaining components to arrive from Thailand (where they are made apparently). Everything checks out thus far, so we may be getting close!!! Maybe this will be a merry Xmas for the M42 afterall.
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oooooohh cant wait. your doin a great job with all this development stuff, but hurry and start FABBIN!! and they say there isnt a santa clause....
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Man that sounds great... i cannot wait to get one.
Keep up the good work man!!
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What country are you in? That makes a difference in the ECU's programming. If it has a 1995 M42 in it, then chances are the ECU ignores any input from the LLCO pin as by then I believe they were all running EGO sensors.
i'm in Singapore. i beleive, our cars are Euro-specs. i'll keep u guys updated on the LLCO cable once i do a diagnostic next week.
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Alrighty...the last component should be in a shipment arriving tomorrow (along with extras to make test units if this one goes off without a hitch). So, HOPEFULLY I will have the car running off of the MAF by tomorrow evening. I also ordered a ton of extra components from Digikey...all the filtering and power supply stuff for more units. Cross your fingers that there are no more...issues with this stupid thing.
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Hokay, update eleventy billion.
I got the parts today and soldered up a little prototype dealy. Works fine, and I got the IAT "dummy" resistor on and at the right value. Tomorrow after work I will look into installing it. Cross your fingers, toes, legs, arms, eyes, whatever!
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Cannot wait for you to finish this. I'm building my paypal account balance in anticipation.
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Well, HOPEFULLY I will test soon.....naturally the car barely ran this morning...and that is stock, just trying to go to work. I do not think I can test the MAF conversion until I figure out why my car was stalling out on the highway and stuff. Details are in another thread.....a "help me plz" thread lol.
EDIT:
Here is the plea for help...
http://m42club.com/forums/showthread.php?p=14582
So uuuh, if you all help me fix this then ummm that means MAF conversions sooner lol.