Author Topic: Misc questions... (Read 5594 times)

a930rocket · « **on:** March 12, 2011, 06:42:45 PM »

I did a search, but couldn't find what I needed yet...

What octane gas is everyone using for the M42 engine? It calls for premium, but is that set in stone? I'm not hot rodding around in the car, so I wonder if a lower octane can be used? Does the M42 have a knock sensor to retard timing for lower octane?

The oil service indicator light and yellow LED stays on all the time, even with the engine off and the keys out. Sometimes the red LED is on as well while driving. I've tried to reset it by some info I found (jumping the 7 and 19 IIRC), but no luck. Any ideas? SI batteries maybe?

What is with the 93 piece hose kit for the cooling system? Mine are all hard and dry (along with the IAC hoses), so I want to replace them all to be on the safe side. But jeez, it looks like a garden hose was cut up and tossed in there. I want to keep it stock, so there's no bypassing it all. Maybe I'm just used to an air cooled car?

A friend mentioned something about the the oil sump pick-up comng loose? Does that sound familiar? What is the repair? PUlling the pan and tightening the bolts down with loctite?

What brand and weight trans and rear end fluid is everyone using?

Last not least, what oil is everyone using (what a can of worms this one is!) The manual says 20w-50, but what about synthetics (5W-30 maybe)? I'm in South Carolina on the coast, so temps are moderate in the winter and can be in the high 80's low 90's in the summer.

Thanks!

a930rocket · « **Reply #1 on:** March 12, 2011, 06:46:04 PM »

I did a search, but couldn't find what I needed yet...

The air bag sensor in the left front engine bay is just hanging there? Anybody know where it plugs in or attaches? Pictures?

My MPG gauge isn't working. It just sits on "0" MPG. Any ideas on where to start?

The oil service indicator light and yellow LED stays on all the time, even with the engine off and the keys out. Sometimes the red LED is on as well while driving. I've tried to reset it by some info I found (jumping the 7 and 19 IIRC), but no luck. Any ideas? SI batteries maybe?

Anybody install a keyless entry system? I found the Omega Research Keyless Entry REC-43T kit for about $35. It seems simple and easy enough to install, but are there better ones? Any directions to hook one up so the running lights flash when locking it?

Anybody re-key the ignition switch? My ignition switch is diffferent than my door/trunk. Two keys are a PITA.

Anybody install one touch window moduals? I found an outfit called Autoloc that has kits to add to the switches. On Amazon cheap at about $55.

Thanks!

monty23psk · « **Reply #2 on:** March 12, 2011, 07:20:33 PM »

I use premium, but for the first 5 years my sister had it before I got it, she used 87 octane. I would not recommend it but it works, just not sure of the damage to the engine.

I had the same issues with the lights and it is the SI board. Batteries are bad. You can try to replace the batteries first before the board.

Hope that is a start.

jscribble · « **Reply #3 on:** March 12, 2011, 07:47:44 PM »

I have run 89 octane, but the car definitely likes 91+ much better. (with chip now I only run 91+) Try to find a station that sells ethanol free too, makes a notable difference in response and mpg.

no idea on the si lights

on the hose set up, this thread should be a good read. I have done this, and like it.

I use synthetic everything, 10w30 royal purple for the engine, and (I think) mobil syn for the diff (90w?)

Oil pickups have been known to be loose, there is a thread on it, but I can't seem to dig it up. Tightening the oil pan (upper) and oil pickup bolts should be on your short list though.

DesktopDave · « **Reply #4 on:** March 12, 2011, 08:42:53 PM »

I run 93 octane, the car gets slightly better mileage with it. I can't figure out why, might be a sampling error in my numbers.

e30's don't have knock sensors. e36's do.

SI batteries aren't that expensive, but they're a PITA to replace correctly. Not worth it, IMHO.

Hoses are a PITA, no doubt. It's a reliable system once you chase down the leaks. Don't take it apart unless you know the plastic bits are in stock, they tend to crack. Or replace them all along with the hoses.

The upper oil pan bolts also retain the oil pickup. It's cast as a single piece. Loctite is the best fix. Just drop the lower pan, tighten the bolts with red or blue, (look for bits of guides & chain links while you're there) & replace the gasket.

Some trannies use gear oil, some use ATF, some use special BMW oil. Mine has the ATF sticker so I use Valvoline synthetic ATF, shifts really well. I use 75w90 synthetic gear oil in my LSD. For motor oil, I use 5w30 synthetic & change it about once a year. It leaks, but it makes the car run well. A thinner oil like this might not do well in very hot temperatures...we usually max out around 80degF avg here...and BMW usually prefers thicker oils. IIRC the owners manual specs 10w40 or 15w50 for your expected temperatures.

DesktopDave · « **Reply #5 on:** March 12, 2011, 08:53:57 PM »

I merged your threads...one was stuck in moderated so nobody could see it. They're pretty similar, sorry for any confusion.

The ABS wire pigtail or the sensor on the inner fender? Maybe I'll take some pics & post them later.

MPG gauge might be damaged, loose wire in the cluster, or the SI board batteries are dead. If it's at 0mpg all the time, it's not getting a speed signal from the diff. Is the speedo working?

There's a post around here somewhere with a keyless system. There was an OEM Alpine option for later e30's. Parking lights can be accessed off the headlight switch IIRC.

You can pull the ignition switch cylinder, same as all other e30's. I'm a bit foggy on this, never done it myself. From what I recall, you get a large paper clip, straighten it a bit. Turn the key to position I (first acc. position) and push the paperclip into the small half-moon indent on the outer ring of the lock cylinder. Turn the key to position II with the paperclip still in, should then come out with the key.

One touch windows would be great. Post it if you decide to order a set.

a930rocket · « **Reply #6 on:** March 12, 2011, 10:33:27 PM »

Thanks Desktop. I tried to split the engine and electrical items into the two forums. Thought it might be the protocol here.

I've ordered the one touch window moduals and the Omega keyless as well. The keyless seems straight forward, but we'll see about the window mod.

I've ordered every hose and fitting thinking that they'll break upon disassembly.

The mpg gauge doesn't move except on start up. It bounces to max mpg, then back to zero. It might flicker every once in awhile.

Bought some 10w-40 synthetic oil. Figure I'll start with it and see how it goes. Went to autozone :rolleyes: for trans and diff fluid. The guy looked it up and it called out hypoid and non-hypoid lube, but the containers were less than clear as to what each was. I held off until I could verify.

The SI light isn't bad, but I'd like to fix it. Maybe if I pill the ignition switch, I'll try to take a look at it then.

DesktopDave · « **Reply #7 on:** March 13, 2011, 07:41:41 AM »

Post some pics of your upcoming adventures. Sounds like you have some fun in your future...

The mpg gauge isn't getting a mph signal, definitely. Since you'll be taking the cluster apart to R&R the SI board, maybe check the pins that connect it to the board. The gauge will slowly bounce from 0 to 40 if it isn't receiving the mph signal from the diff sender. The driver board filters that signal, then sends it to the speedo, the economy gauge and also provides three outputs with the green snap-in adapter installed in models with cruise control.

I'd figure the hypoid is what you want, but I'd assume all gear oil is pretty similar. Hypoid gears are cut in a curved pattern for lower noise, as opposed to straight-cut gears. I'm unsure of what they're talking about, as hypoid diffs are virtually universal in cars. Look on the side of the tranny for a label. BMW spec'ed three types of lubricant for the Getrag 240. I'm not sure why...but I've tried both gear oil (Valvoline synthetic 75w140) and ATF (Valvoline DEXRON II?). The ATF definitely improved shifting in mine.

I've also heard good things about Redline oils, Amsoil (if you can get it reasonably), and an organic alternative I'll be trying soon, RLI in Cleveland, OH.

About the SI board...there are two models, be sure you're ordering batteries for the correct one. Earlier ones had NiCd rechargeables, later ones had lithium non-rechargeables. The two boards are interchangeable in all clusters, but the batteries are not. IIRC, early batteries should test about 3vdc combined, the later batteries should each test out to about 3.7vdc each...if they're still good.

If you're really careful, the cluster can come out with the steering wheel still installed. Though I have replaced the airbag wheel in my car with a 'vert leather sport wheel, so YMMV. If you do decide to remove the wheel, be sure to disconnect the battery so you don't put the airbag light on.

DesktopDave · « **Reply #8 on:** March 13, 2011, 08:30:57 AM »

I found this link recently, looking for info on clusters. It has some great info about the speedo:

Quote

i got tired of my mpg guage and obc speed-related functions not working, so i did a little investigating and now i think ive figured out exactly what happens to the speed signal...

to clarify, the following description is what i have gathered from taking apart my motometer cluster/speedo gauge which is from a 1989 325ix. i dont have experience with the vdo speedo, but will assume its the same until im told otherwise. to the best of my knowledge this is what happens (in great technical detail):

(1) raw signal from speed sensor is brought into the cluster (BR/RD wire, pin 12, C2 connector/white plug)

(2) it is routed to the speedometer gauge (pin 31b)

(3) the raw signal goes into a chip (pin 9, UAF 2115 speedometer chip, datasheet)

(4) pin 3 on the chip is the "signal output". from what i can tell from the chip’s datasheet, its the same signal, just with some added short circuit/overload protection. basically an isolated version of the raw signal coming from the speed sensor.

(5) pin A on the speedo is connected directly to pin 3 on the UAF2115 chip.

(6) pin A is routed to pin 10 on the C5 connector (service indicator board) and to pin 26 on the C3 connector (BR/RD wire, runs to obc). Also, it is routed to the green plug that sticks out of the bottom of the speedo (on mine there is one wire attached to one of the 3 inline pins on the right side - doesnt matter which pin, those three pins all share the same connection)

so, in summation of that last step, the processed “signal output” is what is sent to the obc as well as the service indicator board (mpg gauge). AND, assuming you have a properly functioning speedometer, the group of three inline pins on the green connector on the back of the cluster are the processed “signal output” as well.

this UAF2115 chip also controls the stepper motor for the speedometer. basically, if this chip goes bad or is faulty - anything that relies on the "signal output" coming from the chip could cease to function -> speedo, obc speed related functions, mpg gauge

a930rocket · « **Reply #9 on:** March 13, 2011, 07:06:51 PM »

Thanks for the info. I'll check it out when I get into.

Anybidy know how to remove the ignition switch cylinder? I believe there is somthing about inserting and turning the key, then using a paper clip or similar in the small hole in the face of the switch to release the cylinder. I tried it, but it didn't work. Any advice?

I swapped out the air filter and boot between the MAF and the TB tonight. I noticed there is a lot more stuff in the way to get to all the cooling system hoses, etc. Would it be easier to remove the intake or just replace what I can? Not knowing how old some of the hoses are, the safe thing would be to swap them all out I'm sure.

Tomorrow's the oil change and gas filter. When the rest of the coolant hoses get here, I'll be up under the car to change fluids and to see what all needs to be done there (bushings, etc).

DesktopDave · « **Reply #10 on:** March 13, 2011, 07:50:02 PM »

Everyone pulls at least the upper half of the intake to get at the hoses. There are four gaskets (lower intake to cyl head, upper intake to lower intake, and two for the throttle body). There's a few great threads here about cleaning up the intake, deleting the throttle body heater, upgrading to newer Bosch four-hole injectors, etc.

I'd order the two lower gaskets & new injector o-rings. The two gaskets on the throttle body are metal and generally reusable.

a930rocket · « **Reply #11 on:** March 14, 2011, 04:39:28 AM »

Sounds good. I read the info on cleaning up the hoses and deleting the heater plate, but I'm determined to keep this one stock or stock looking.

To be on the safe side, I'll order new gaskets as well. I doubt any local parts place has what I need and I don't want to stop mid way through to order parts.

a930rocket · « **Reply #12 on:** March 14, 2011, 02:10:30 PM »

Got the ignition switch out, but my locksmith couldn't figure out how to seperate it to re-key to the door locks.

Anbody ever rekey the ignition switch?

Thinking about it some more, why can't the dealer get me a new ignition cylinder based on my car's VIN?

BTW. Once I got it out, there were some other parts in there that lock/unlock the steering wheel and were spring loaded. I couldn't figure out how to get it back together with the spring, etc, but it's in and working.

bmwm42 · « **Reply #13 on:** March 14, 2011, 03:01:55 PM »

i run 89 octane in mine and get 35 mpg hwy no knocking and clean internals i do have a cop kit though so that might also be helping with the lower octane but im happy with that octane level at the moment

a930rocket · « **Reply #14 on:** March 15, 2011, 03:58:10 PM »

Went to the dealer today and was able to order a new cylinder and key based on the VIN. Should be here tomnorrow or the next day.

I wouldn't have thought about using a lower octane, but gas prices are going up by the hour it seems. On my turbo, I used nothing but 93 for the street and 100 at the track (and at 3 mpg and $7 per gallon, that gets expensive going 300 miles on a weekend!). I don't think I've taken the rpms past 3500 since I bought the car a few weeks ago, as it's just a get around car...