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BMW: BMW with NO FIRE!!!, oil seperator, bosch platinum


Question
I appreciate your advice and I will try what you said however, I did make sure the coil packs were grounded, what I did was pulled a plug also and grounded it with the coil pack intact... Still no fire!  The DME/EGS BOX is located where? because I took the main computer out that was in the firewall, opened it up and all looked OK except for a few white solder joints that I very carefully fixed.  Anyway, where is this thing located and I will try it... I also tried the relay and hoses as you suggested and they too seemed to be fine... I appreciate your help and suggestions...
Frustrated,
JOE
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Followup To

Question -
I have a 1994 BMW 325i with the M50 engine... I was driving it and it stopped on me twice at an idle. Every time it stopped, it cranked right back up... I drove it home and parked it. After two days, I went out to start it and nothing!  The fuel pump is pumping, but removing the coil packs one at a time on several of the cylinders, I found there was no fire... Is there a sensor that can cause this, or is my engine computer gone?
PLEASE HELP!
Sincerely,
JOE

Answer -
Sorry to hear about the car troubles. The first thing I am thinking is you can't really check the coils for fire if they are not mounted in the valve cover, they need to be grounded. There are a number of small things that could keep that car from running. The first thing I would check is vacuum lines. There are 2 that run from the valve cover to the oil seperator under the manifold. They get rotten and break or clogged with oil sludge. Check those and you might as well replace them because they will probably break taking them off. Next would be the spark plugs, the porcelain tends to crack where the coil boot goes over them. Pull the plugs and look for vertical brown or black carbon tracks on the white porcelain. If you see any replace the plugs with bosch platinum plugs and the coil boots on the cracked plugs. Then if it still won't run check fuel pressure, you may have a clogged fuel filter or low volume from a worn out fuel pump. That recently happened to my e36, it would get sluggish here and there and die occasionally then one day it just wouldn't start even though the pump was running. Maybe the DME main relay. It is next to the fuse box under the hood. It has a plastic cover that you can take off after the main fuse box cover. I think the DME relay it the middle one and you can't change it with any other in the car to see if it works. Just take it out and bang on it and put it back in and try it. My last guess would be the DME. The drains for the DME/EGS box sucked and would get clogged or just not be able to drain a lot of water. The DME is the lower module in the bracket. If you have to take it out take the covers off. It takes a T20 torx and pliers to break the tabs (the tabs are supposed to break) If you see green corrosion in it then you have a dead DME. Good luck and if you need any further tips or component locations let me know.

Answer
Joe,
Sorry for the confusion. The DME is the main engine computer, in domestic produced manuals or OBD terms the ECU. That is probably the module you found. It is behind the foam cover that covers the plastic cover in the firewall next to the passenger hood hinge. It is still possible to have a bad engine computer even without corrosion on any terminals. My only guess to eliminate that would be to find another DME with the same part number from a close to identical car as possible. It will have to have the same trans and within a few months production date as yours. Another thought would be the camshaft sensor or even the crankshaft sensor. Without a reference as to where the crank or cam is the DME will not fire. I would try a cam sensor first as those tend to go bad more. It is the sensor on the front of the cylinder head next to the vanos unit. Also don't rule out the DME main relay yet, it may just be completely dead. This is going to be difficult without the dealer scan tool since it is not an OBDII car and auto zone can't rear the codes. Possibly tow it to the dealer and have them diag it for 1/2 hour labor then I can help you change whatever they tell you it needs. Sorry I can't be more help.