fuel pump/non-start issues - been doing lots of research, still NEED HELP... please >

[CCE30]

Thanks again Mike.

It turns out the sensors were fine.  I was using a very very old multimeter and I forgot to calibrate it.

Back to the drawing board.  Bummer. . . .

[roundel318]

is the underside PCB of the fusebox cracked, etc?

[Wizard]

Any one have a CPS I could borrow (or buy)?...NEVERMIND....Got one coming from Zygmunt...

Thanks,
Dan

[Half8]

Resurrecting the best diagnosis thread out there. . .

Here's my story.  I bought a '91 318iS with 114k miles about 3 weeks ago.  It had run flawlessly.  (The only exception is when starting cold, it would stumble once or twice before settling in to a nice smooth idle.)

Earlier this week, I was driving home when the car hit a decent-sized bump, and the engine stopped dead.  After coasting into a parking lot, the car would crank, but not fire.  After getting towed home, I found this thread and started running through some of the diagnostics.  Here's what I've checked so far:

1. After removing the rear seat and the fuel pump access cover, there's no sound coming from the fuel pump with the key on.

2. Stomp test gives me the 1444

3. Crank position sensor reads 550 ohms

4. Cam position sensor reads 1150 ohms

5. Fuse 11 is fine

6. I get no voltage at the fuel pump harness connector with the fuel pump relay installed and key on

7. I do get proper voltage at the harness connector with tabs 87 and 30 jumpered and key on, but the fuel pump still makes no noise when the wires are reconnected.  Still no noise when jiggling the wires.

8. Fusible link doesn't show any obvious signs of having burned up

9. Check engine light does come on with the key in the on position

10. I haven't removed the fuel pump to test it externally because the gas tank is all the way full.  As soon as I loosen the nuts holding it in place, gas starts leaking very quickly.  

Putting all of this together, I'm led to believe that I have a bad fuel pump relay (6 & 7 above), and that I have a bad fuel pump (7).  Is my logic sound enough to warrant ordering up a new fuel pump and relay, or should I perform more tests first?

Thanks in advance!

[RED IS 91]

If you have 12 volts at the connector and the pump is not humming or making some kind of noise then it's probably done for. You could hook 12 directly to the pump to see if it will start but it doesn't sound hopeful. Time for a new pump and at least you can rest easy that it will be good for another 150,000 miles.

[locknload]

Mine did exactly the same thing a year ago.  Hit a bump, actually, more like an expansion joint.   I wouldn't have even noticed it except as you say, the engine died immediately.  It was indeed a dead fuel pump.  If your tank is too full, try jacking the passenger side of the car to raise the pump side enough to get the pump out without making a mess.  If that doesn't work, try siphonng the gas out through the fuel pump exit.  Also, find a DIY thread on removing the pump as it is tricky and involves some odd twists and contortions of the pump as it also holds the float (I think), or is quite near it.

[Half8]

Mine did exactly the same thing a year ago.  Hit a bump, actually, more like an expansion joint.   I wouldn't have even noticed it except as you say, the engine died immediately.  It was indeed a dead fuel pump.  If your tank is too full, try jacking the passenger side of the car to raise the pump side enough to get the pump out without making a mess.  If that doesn't work, try siphonng the gas out through the fuel pump exit.  Also, find a DIY thread on removing the pump as it is tricky and involves some odd twists and contortions of the pump as it also holds the float (I think), or is quite near it.

Replacing the pump with a good used pump worked for me, but now I'm throwing a CEL at idle.  Prior to the fuel pump failure, the car would stumble a few times on a cold start before settling in to a nice smooth ~750rpm idle.  There were no CEL issues and no stomp test codes even with the dead fuel pump.  

Now the engine stumbles harder and longer after a cold start.  Even after it's warmed up, the check engine light comes on when idling for about a minute.  Tapping the accelerator makes the CEL temporarily go away until the next time it sits at idle for about a minute.  Stomp test gives me the ever-popular 1222 lambda code.  Aside from the CEL, the engine runs smoothly and accelerates fine.

I found some split hoses under the intake, and patched them up with duct tape, with no effect on the cold start or the CEL.  Adjusting the throttle to give a higher (1000rpm) idle had no effect on the CEL.  Even at the higher-rpm idle, the CEL will still come on, while a quick stab of the throttle clears the light.

Any ideas on what might be the most likely culprit for the 1222 code before I start running through the whole list?

[RED IS 91]

Have you cleaned the ICV (idle control valve)?
When  was the last time the O2 sensor was replaced ?

[Half8]

Have you cleaned the ICV (idle control valve)?
When  was the last time the O2 sensor was replaced ?

Cleaning the ICV stopped the cold-start stumble, and I haven't seen a CEL since cleaning it.  I had to give it a thorough soaking with carb cleaner, and essentially "jump-start" it by apply 12v directly.  After a couple of rounds of that, it finally started to hum again when reconnected in the engine bay.  The bad news is that it only gave me a reading of 8 ohms, so I will need to replace it.  But at least now I can keep driving it while I assemble the "mess under the intake" materials.

[Victorymike18]

My M42 Powered E30 recently died in similar fashion.

After reading this thread, I went out and checked the resistance of the Crank Position Sensor, and it read high.  I traced the wire from the plug (under intake manifold) down to the sensor head and found that the wire was rubbing on a pulley and wore through...

Now, can anyone point me to a reputable online vendor that sells the Crank Position Sensor for a reasonable price?  (The Cam sensor is easy to find, but Crank Sensor seems elusive).   It's part number 12-14-1-721-968

Someone linked BAVauto which has it listed for $155.  Is there any place that has it for less?
Pelican Parts lists it as a special order part, at dealer pricing of $177

On a similar note:   Here is the Real OEM diagram that has the part number for the Crank Postion Sensor
(Item#11 "Pulse Generator")

http://www.realoem.com/bmw/showparts.do?model=AF93&mospid=47305&btnr=11_0156&hg=11&fg=10

[RED IS 91]

I don't recommend using cheap parts but here ya go............

http://www.partsgeek.com/catalog/1991/bmw/318is/engine_mechanical/crank_position_sensor.html

[Cobra Jet]

When my CPS went south, the best price I found was through http://www.bimmerparts.com.  The part is NOT listed on their site (at least not at the time when I was looking), however, I just emailed them and gave them the CPS part number and also stated I needed the Crank Positioning Sensor NOT the Cam Sensor.  IIRC, I think I had paid $160 which included shipping costs to NJ.  I ordered from bimmerparts only because I have ordered many BMW parts from him in the past, never had an issue, parts are genuine, shipping is quick and customer service is excellent.

FYI - http://www.realoem.com shows the genuine BMW Crank Positioning Sensor as the "Pulse Generator", so if your BMW Dealer cannot locate the part as a "CPS" or "Crank Positioning Sensor", tell them to look up "Pulse Generator".  It is BMW part # 12141721968.  

It is part # 11 in this schematic diagram on realoem:



That CPS is NOT cheap.  If you have a BMW CCA Member #, you can get a discount on the part at your local BMW Dealer - but then again, every BMW Dealer can charge their own price for the part, since they are independent Dealers and don't follow a standard price structure.

This thread has a TON of excellent tech for the non-start issue - if you have completed all of the process of eliminations of the other parts for a non-start issue and the car still will not start, 98% of the time, it's going to be a dead CPS...  and for whatever reasons unbeknownst to all of us, that M42 DME will NEVER spit out a failure code for a failed CPS, even though an actual code exists...  I guess the BMW programmers forgot to hardcode that one into the M42 DME's... LMAO...

[Cobra Jet]

I don't recommend using cheap parts but here ya go............

http://www.partsgeek.com/catalog/1991/bmw/318is/engine_mechanical/crank_position_sensor.html

JUST AN FYI!!!

That pic or part in that above link is totally incorrect for the M42 E30 Crank Positioning Sensor!  BE AWARE of what you're buying, because some of these BMW aftermarket vendors are showing totally incorrect parts for the E30 M42 engine...  The correct sensor should have a very long black wire attached to it (about 3ft+), with a male connector end which gets connected to the black electrical distribution box located under the intake, on the driver's side of the engine...

[RED IS 91]

JUST AN FYI!!!

That pic or part in that above link is totally incorrect for the M42 E30 Crank Positioning Sensor!  BE AWARE of what you're buying, because some of these BMW aftermarket vendors are showing totally incorrect parts for the E30 M42 engine...  The correct sensor should have a very long black wire attached to it (about 3ft+), with a male connector end which gets connected to the black electrical distribution box located under the intake, on the driver's side of the engine...

If you read under the image at that link  it states "Image is not vehicle specific" which means it is not the part you'll recieve. I suggest if you have any questions for them to call them with the part number and describe the part.

[Cobra Jet]

If you read under the image at that link  it states "Image is not vehicle specific" which means it is not the part you'll recieve. I suggest if you have any questions for them to call them with the part number and describe the part.

D'OH!  I did not see the "fine print"....  but anyhow, as you also said too - for those seeking to buy that part (which is awful cheap), definitely make sure it's the correct CPS (for an E30 M42) and not for an E36 M44...



take care!