Yes, another crank no start.

[Dusty B]

First post here on M42. First off I'd like to say that this is a great community. I've lurked for a while and found vast amounts of very useful information. This is my first BMW, but not my first car that I've had to work on. I'm a little behind on the "quirks" of the bavarian nature but give me a little slack please .

Secondly, I'd like to apologize for another crank no start thread. Mods, please move if in wrong section!

Vehicle in question is 91 318is. m42 engine equiped (think a junkyard motor, yellow chaulk numbers on timing cover)

As stated condition is crank no start. This is how I picked up the car. Dead battery when I inherited the car so no stored codes but the "1444" from stomp test. Previous owner stated he drove the car home one night, went out next morning and never started again. I went through the normal look over for fusible link issue, but all was well there. So onward I went.

Have good compression at all cylinders ~170 accross the board.

Great spark at all cylinders. Coils have sufficient voltage at thier respective connectors. All correctly connected.

Have fuel. Bench tested every piece of fuel delivery system, have checked all vehicle wiring. Pull the supply hose before rail, and it'll fill a 2 liter bottle with ease when cranking not to mention soaking the plugs while trying to crank to start when connected. Return line clean and clear.

Crank sensor ohms out a little low, around 505ohms. I know this is lower than expected, but have read many posts of people have this or lower and still been able to start. Cam sensor ohms out perfectly at 1250.

Have checked mechanical timing. Timing chain is taught and timing is dead on correct.

So now I'm leaning to an electrical/engine management issue still. I realize it still may be the crank sensor, so I'm thinking about picking another up today just to ease my mind.

The one thing that got me though.... I pulled the fuel pump fuse. This had/has no effect on the cranking of the vehicle. I decided to shoot some starting fluid in the intake to see if she would "pop" over. Well she popped alright, back through the intake with a fireball into the engine bay. Luckily I'm very careful with flamables and everything from previous tests was cleaned properly. So this leads me to believe electronic timing issue. I don't know enough about the m42 timing yet to verify if any intake valve should be open at all when spark is being introduced, especially at a start/idle standpoint.

I'm just a little stumped. All the right ingredients, but no succesful shake and bake!


Thanks in advance for any help/replies.

[Geoff]

it sounds like you have covered a lot of bases, so if you are correct that its a timing issue, yet the mechanical timing  of the engine is correct, that leaves you with the only real variable in the equation...the puter...yes, that lovely little device lurking above your glove box has been known to sometimes take a dump, and when it does the only thing to try is another one, hopefully one that is known to be good from a running car, or as supplied by possibly a helpful board member, I dont have an extra or I'd offer it.  They are usually pretty reasonable in cost.    Good luck,
                                                                       Geoff

[Dusty B]

it sounds like you have covered a lot of bases, so if you are correct that its a timing issue, yet the mechanical timing  of the engine is correct, that leaves you with the only real variable in the equation...the puter...yes, that lovely little device lurking above your glove box has been known to sometimes take a dump, and when it does the only thing to try is another one, hopefully one that is known to be good from a running car, or as supplied by possibly a helpful board member, I dont have an extra or I'd offer it.  They are usually pretty reasonable in cost.    Good luck,
                                                                       Geoff

Geoff,

Thanks for your response. It's helpful to have the experts confirm I'm going in the right direction.

The next embarrasing thing on the list now.... My glovebox won't open! haha. Discovered this the other day before I actually started trying to get the car to start, was just giving the EXTREMELY clean interior a once over and clean out. Figured I'd empty the glovebox of it's contents and currently is inaccessible. I'll get that sorted out one way or another though....

Has anyone seen an e30 act like this with a supposidly good grand sensor?

Anyone seen this behavior with a bad pcm? Mainly the popping back through the intake?

If anyone relatively close by or further away would lend me either/or/both a crank sensor or computer I'd be indebted forever. I'd be willing to send/give a deposit or core fee for any items borrowed.

[bme30]

Did you pull one plug wire at a time and check if you are getting a spark?  

I had this happen to me as well but it turned out to be the fuel pump... I know yours is good.

Good luck

[Dusty B]

Did you pull one plug wire at a time and check if you are getting a spark?  

I had this happen to me as well but it turned out to be the fuel pump... I know yours is good.

Good luck

All plugs getting spark. Removed from engine, and grounded against shock tower mount bolts. All producing great spark.

The one thing I didn't do, since it's in storage, was throw a timing light on this thing.

I'd imagine even at slow cranking speeds I'd be able to see an... erractic light pulse?

[deansweet]

I'm with Geoff on this one.
you have done everything that I would have done including shooting starting fluid straight in to intake.
ECM's aren't hard to find on the cheap so I'd try that?
Now on to your glove box? Makes me think of a treasure chest?! Who knows what's in there?! Get that open asap and tell us of your riches?!

[Dusty B]

I'm with Geoff on this one.
you have done everything that I would have done including shooting starting fluid straight in to intake.
ECM's aren't hard to find on the cheap so I'd try that?
Now on to your glove box? Makes me think of a treasure chest?! Who knows what's in there?! Get that open asap and tell us of your riches?!

Yeah I'm going to just start looking for a known good ECM and try that first I guess. Any vehicle specific info I need to source a used one or is it just a matter of pulling a serial number or part number off of the existing unit?

Edit: If it's a production date thing it was built  05-28-1990

Anyone reading this have a good spare for sale or test?

As far as my riches go, with my luck I'm likely to find a live bear in the glove box after I've somehow managed to get honey on my back unknowingly.

[Dusty B]

Also, no thoughts on my low-ish resistance result of 505ohms?

[colin86325]

Seems ok to me.  I think the spec is 540 +/- 60 ohms.

[Dusty B]

Still looking for an ECM for my gal.

Think I'm going to stop at foreign car parts on the way home and pick up a crank sensor even thought it's within spec.

[sfinsf]

I was able to test out two different ecu's during my no start. They unfortunately were not the issue. Try posting on forums that you only want to borrow, I paid for shipping only on mine. Local parts place would not allow me to return electronic parts after purchase.
I had a CPS that would pin out ok but was not opening and closing for some electrical reason. I'd remain focused on the puter and the cps.

[Dusty B]

I was able to test out two different ecu's during my no start. They unfortunately were not the issue. Try posting on forums that you only want to borrow, I paid for shipping only on mine. Local parts place would not allow me to return electronic parts after purchase.
I had a CPS that would pin out ok but was not opening and closing for some electrical reason. I'd remain focused on the puter and the cps.

So you were getting fuel like my situation but the CPS was still at fault?

A member on this board has a puter for sale for 45 bucks. If for nothing else probably worth it just to have a spare.....

[colin86325]

Also check the distance between the sensor and the teeth on the tone wheel.  I don't know the spec offhand though.

[Dusty B]

Also check the distance between the sensor and the teeth on the tone wheel.  I don't know the spec offhand though.

I couldn't find a spec either....

I did clean the sensor tip off, and used a little emory cloth to just clean the surface rust off the tone ring teeth.

I really with I still had a graphing multimeter and could watch the digital signal on this thing....


EDIT: Just ordered a cps from foreign car parts. It's an aftermarket. I know the guys down there pretty well, said they haven't encountered any issues with selling this aftermarket unit. It's still 90 bucks though, and it's being transfered from the warehouse so I'll be able to pick it up on way home after work. The bosch sensor would have taken 7-10 days to get, and lets be honest, at this point I'm impatient haha.

If by some miracle this aftermarket cps solves the problem I'll let you all know.

[Dusty B]

So I'm in the garage as I write this. Installed new CPS. Same no start condition. Getting discouraged....