Having some engine trouble.

[porsche gt1]

bmw anything is bloody expesnive

except fan clutches, they have the best price.

[porsche gt1]

i read somwhere about the fuel systems having trouble on E30's when its below half a tank some times, the pump can't hold the presure cause of less fuel, top it off or clamp the return line and see if she winds up, also im more partial to the chevron gas... anywho sounds fuel related, i have that problem as well but its only when i first start the car and its at the low RPM's not the the high... anywho good luck to ya

I agree shell is the S%$t's, I only use chevron and I have had no issues.

[O 16581 72452 5]

Glad you kept posted on this thread until you found the cause, if you would, edit the first post with the conclusion. It seems to be a common problem and would've saved me about 20 minutes if i would've read it on the first page.

I will check this out tomorrow, my car is doing the exact same thing your's is, i changed my spark plugs and it helped a little, but still there.

[Fred]

Glad you got it all worked out.

[AdamF 88iS]

My M3 did the same thing, it was the AFM for me too. Ran great all the way until about 6k then it just runs out of steam all of a sudden.

[kowalski]

ill second that

[Nick325is]

I think he is talking about the AFM circuit board. He bent the pins you see to the left of the picture so that they don't touch the broken part of the track.
Jordan...I am very happy to see you figured this out. I will be looking at my AFM this week.


Nick

[kowalski]

the throttle positioning sensor right? theres contacts i think he bent them so they would make contact again.

[diegom6]

Jordan could you rephrase or someone else this??

I bent the heads to contact off the worn portions of the track, and it now pulls hard all the way to redline. Clean and smooth

I don't understand what you mean and would liek ot know if ever happens to me!

[kowalski]

right on!

[rumatt]

Wow. Glad you got it figured out.

[Jordan]

Well nooo one is replying, just the same.

This was my problem. I bent the heads to contact off the worn portions of the track, and it now pulls hard all the way to redline. Clean and smooth.

Its amazing how much smoother in general the engine pulls throughout the rev range.

[Jordan]

So the car is still freaking doing it. Very annoying.

I checked to make sure both the main fuel pump, and the transfer pumps are working. They are.

I was unable to rest the fuel pressure because the guage I have available to me at work has a stupid GM fitting stuck on it.

I did test the AFM tonight, and came to some conclusions. I'm pretty sure its got issues, and is the likely cause of my problem.

at rest the AFM is showing ~3.50k ohms. It raises fairly steadily up to ~4.70k ohms, just before the spot in question. Once the head goes into this spot it drops to ~0.70k ohms, and in one spot inside it... full continuity.(0ohms)

Here is a large picture of the AFM circut board, the section in question is show larger, and brackets surround it.

http://www.r3vlimited.com/Images/AFMboard.jpg

I don't see how this can not be my problem, seeing as this is the WOT range. Engine suddenly thinks its getting no fucking air, then cuts the fuel to match? Hence why the engine will not accelerate.

Input!

[oh2fly]

Okay, you are getting somewhere. If the car pulls harder at part throttle than full throttle, that means a fuel problem. You are putting in more air at full throttle and the fuel isn't increasing to keep up. See if one of the techs at work has a mechanical fuel pressure gauge you can borrow. Tee it into the pressure hose and tape the gauge to one of your wiper arms. Test drive time!. Pressure should rise under load and drop on decel. Should hit 40 psi under load. If that is fine, maybe a plugged filter restricting flow. You can check flow by jumping the fuel pump relay and aiming the return hose into a container. It should be a healthy stream. Besides pressure, you need volume. The TPS still may be bad, not giving you enrichment at full throttle. I check this by hooking my Vantage up to the oxygen sensor wire and watch the pattern. Thd normal waves switch to a flatline with a number around .800 volts. indicating a rich condition. I have an ecu you can try. Good luck!

[Nick325is]

Hmm, so the FPR made it better. I may have to try that out.


Nick