Can Someone please help !!!!
I have a 1987 BMW325i cabrio, it only has 70k on it & one lady owner from new ,the
car sat for five years until i purchased it the car will only run with the mass air sensor
connecter pulled out , i have replaced the TPS,the idle control valve , the rubber boot
but i got another mass air sensor from the junk yard so i have two used ones as soon
as i plug it in the car dies .if i start the car with it plugged in it will start immediatly but
then die .Any ideas???i have the car for sale and need it running
Did the lady seller say why it sat unstarted for 5 years? BTW nice looking car.
I don't know if this helps, but I had a Toyota with the same problem, found out that there wasn't enough air flow through the MAF to move the vane at idle so it just shut down, checked the engine vacuum and it only had 15 inches at idle, it shouldn't have even ran but it did, wound up replacing the engine, it only had 85 K but like yours it sat a lot, we thought that the rings might have collapsed due to lack of use, after engine replacement it worked just fine, weird.
The engine runs with the mass air flow sensor unplugged so it cannot be rings . The car was sat because the ladies husband had a stroke she has been a client of mine for years and I've asked to buy it from her year after year . It's something simple that I'm missing !
T.S. has a good place for you to start. Check your vacuum lines. Since the previous owner didn't park it for a reason of it being a problem. I'm with you. Something simple.
PCV would be my first suspect, then the vacuum hoses, I am not too familiar with BMW computer systems but there should be a diagnostic flash out code system, that might help if you could acces that system. There weren't too many Beamers in my area as the closest dealer was over 100 miles away.
So both mass air flow sensors have the same results?
Yes both of them . I didn't want to fork out 150 for a new one if I didn't have to
Yes as the problem is either a vacuum problem, ECM, or wiring.
Ok I'll keep trying . Thank you all !!!
Remove the ground strap between the oil pan and the frame and clean all the oil and corrosion from the ends. Re-installed it and see if it fires up. It could also be a fuel pump relay, fuel pump (there are two), the main engine relay, the Engine Control Module, the water temp sensor, cold start valve, blown fuse, distributor cap and rotor, plug wires, timing belt damaged. Here are just a few things that can be causing the no run issue.
Buy a new MAF sensor!
sounds like a fuel pump relay, the engine goes into default mode when maf is unplugged, bypassing the relay and keeping the pump pumping constant (and your gas mileage is probably horrible and it probably runs rough at certain speeds). It has an erratic signal when maf is plugged in, thus no or very little fuel pressure.
or it could be a filter or pump itself, but id try the relay first.
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