1988 528e hesitates after engine has warmed up

[afpffi]

1988 528e hesitates after engine has warmed up (I have the fix)

Hi All;
I have a 1988 528e that has a problem running stead after its at operating temp.
I have replaced all tune-up parts, checked fuel pressure and all vacum lines, and still have the same problem.

If any one out there has had this same problem and you found a solution please let me know.

Thanks

afpffi

 

[Likster]

Wasssup Afpffi I have the same car, I fixed mine by replacing the O2 sen and adjusting airflowmeter. Adjusting valves helped too. Open throttle body and clean w/carb or either spray and a toothbrush
[fake] brush it's teeth LOL

 

[afpffi]

Hi likster;
Thanks for the feed back , but I did all of the above and some. All parts work to spec's. The car runs get when you start it , then after 10 min. it starts acting up. I guess I will have to get use to the idea not to travel for more than 9.8min from home.

Thanks

 

[BMWJohn]

I Share Your Frustration!

Hi likster;
Thanks for the feed back , but I did all of the above and some. All parts work to spec's. The car runs get when you start it , then after 10 min. it starts acting up. I guess I will have to get use to the idea not to travel for more than 9.8min from home.

Thanks

Hey, I have an 86 528e with the same problem. I have never had such difficulty diagnosing an engine problem! Just like you, I have been through all the normal diagnostics including, replacing fuel pressure regulator, thermo time switch, and fuel pump relay and absolutely no improvement. Car starts hesitating a bit at 55-65mph on freeway after 15-20 minutes of driving and will sometimes die at idle (lots of fun). After turning engine off for even a few minutes it is almost impossible to start (sounds like it is trying to run on 2-3 cylinders and spews black smoke). After sitting and cooling completely down it will start and run normally for another 15-20 minutes.

I'll let you know if I discover anything that helps!

John
San Rafael, CA

 

[Likster]

Wiggle test

OK EVERYBODY READY TO TRY THIS ONE,... SEEMS TO ME WE ALL KINDA HAVE THE SAME PROBLEMS,... UNDER THE DASH THERS A PLASTIC CONNECTOR WITH THESE SMALL SHITTY PINS THAT BELONG IN MY PALM PILOT. I DID AWAY WITH THE WHOLE CONNECTOR WENT TO RADIO SHACK AND FOUND ME A CONNECTOR WITH BETTER CONNETIONS. REWIRED THAN WENT TO JUNK YARD AND GOT ABOUT 3 MAIN RELAYS AND FUEL. (NEXT TO FUSE BOX ENGINE COMP.)

AFTER THAT I BEGAN TO GET RESULTS. LOW SIGNAL TO MAIN AND FUEL RELAYS. WHILE CAR IS RUNNING GRAB HARNESS AT STOCK CONNECTOR AND WIGGLE. This my friends is called the wiggle test

 

[afpffi]

Hi All;
Well it doesn't look good! I tried every trick in the book and even some that they would not mention, it all comes down to one thing the ECU.

If you open the glove box and pull down the cove to expose the ECU ( while the car is acting up ) you will notice that it is rather HOT HOT HOT ( as they say in Miami ) this is why we are having trouble ( Maybe ?). I have not replaced mine yet, I have yet to find a replacement to try that will not cost an arm ,leg and 3 toe's.

If any one has a good parts supplier let me know.

ECU - 0261200154

 

[ronskal]

My first post here. If you think the ECU is overheating and causing your problem, grab a computer cooling fan and tape it up to the bottom of the ECU and wire it up to some available power. These fans can be had in 12 volt versions probably at Radio Shack for a couple bucks. If you duct the airflow to blast cool the ECU, it should at least delay this hesitation problem, confirming the ECU as the culprit.

 

[afpffi]

Well here I go again; it’s not the ECU (Electronic Control Unit or Computer).
I put down my $ for a new Mass Air Flow Meter and a New ECU and it didn't work.

I have read just about every listing from different Forums and it all come back to fuel pressure or Fuel Pressure Relay.

When do you call it quits? The car is in great shape, and when it run it runs like a bear.

Maybe it's time for the For Sale sign

 

[afpffi]

The Problem is solved

Well I found it, and not on my own ($ 1234.13 later).I had to bring it in! the frustration the disappointment (OH THE SHAME ), But the dealer knew what it was (a well guarded secrete of BMW), 2 days of diagnostics By a mechanic that did every thing I did but charged me $129.00 an hour and then to wait for the return of an old timer that fixed it in 15min while drinking his cup of dunkin donuts coffee (large Medium 1 sugar).

And for $19.95 [80?] You can know the answer to.

E-Mail For details-
Fairfieldind@yahoo.com