928 Fuel system shutdown -- 928S4VR Forum

[ Show ]

Support VoyForums

[ Shrink ]

VoyForums Announcement: Programming and providing support for this service has been a labor of love since 1997. We are one of the few services online who values our users' privacy, and have never sold your information. We have even fought hard to defend your privacy in legal cases; however, we've done it with almost no financial support -- paying out of pocket to continue providing the service. Due to the issues imposed on us by advertisers, we also stopped hosting most ads on the forums many years ago. We hope you appreciate our efforts.

Show your support by donating any amount. (Note: We are still technically a for-profit company, so your contribution is not tax-deductible.) PayPal Acct: Feedback:

Donate to VoyForums (PayPal):

[ Login ] [ Contact Forum Admin ] [ Main index ] [ Post a new message ] [ Search | Check update time | Archives: 1, 2 ]

[ Next Thread | Previous Thread | Next Message | Previous Message ]

Date Posted: 06:38:26 06/16/04 Wed
Author: dan baker
Author Host/IP: 67.136.83.63
Subject: 928 Fuel system shutdown

928 Porsche Fuel injection system shutdown.

�You have twice as much good luck as you have bad luck.� �Chinese proverb

A complete shutdown of the fuel injection system in the 928 is often caused by a circuit failure in the ECU or brain. The brain is located behind the passenger side kick panel, and is the larger of the two control units. Naturally, it�s the hardest one to remove.

Failure symptoms may include a shutoff of the fuel pump, and a woodpecker noise in the intake manifold during cranking, and intermittent stalling. The car will often idle but will die whenever the throttle is opened. Onset can be sudden, or produce a lingering intermittent stalling problem.

First impulse is to test the pump and pump relay, but hot-wiring the pump itself can test this. If the pump runs, and If the car still won�t run above idle, in all probability it�s the ECU. The Bosch ECU used a hybrid circuit board in the 928 that produces the above condition when it fails. Parts sources will quote you between $750-$1400 for a rebuilt unit which will send you flying to the Internet.

During my search I ran across an important article on the serious, car killing flex plate design problem in automatic trans 928�s, so I called the originator of the article, Exotic Motorwerks in Phoenix. I asked about ECU re-builders and they kindly referred me to Richard Andrade and Electronik Repair in Mesa, Arizona.

Richard is a well known 928 enthusiasts and electronic engineer. He has studied the problem and developed a rebuild with a master ECU rebuilder in Europe, that replaces the faulty hybrid circuit with vastly more reliable components. Total cost was substantially less than the quotes I had in hand, and turnaround was two days! I was able to get back on the road, avoid storage charges, and I learned a lot about the 928 in discussions with Richard. By the way, he is looking for a few cores so if you happen to learn of an orphaned 002-504 series 928 ECU give him a call.

Further, Richard produced a very comprehensive PDF file to troubleshoot the ECU problem, which is attached. If you are going through an older S4 you might consider this as a preventative procedure, as many ECU�s are failing in the 928, and the problem is not something you want to deal with while breaking in a new romance on a road trip.

Richard is prominent in the national 928 club and both knowledgeable and helpful. His website is: WWW.electronickrepair@earthlink.net

Ask Richard for a PDF copy of his article on the flex plate tension problem in auto trans cars, and check for this condition on your car. Un-corrected this problem can lead to the complete loss of an engine, which is a memorable inconvenience in a 928. Now, for those of you who would like to sign the ballot initiative to eliminate the California Highway Patrol, break into groups by first letter of last name�

Dan Baker
Lake Havasu, Arizona

[ Next Thread | Previous Thread | Next Message | Previous Message ]

Replies:

Re: 928 Fuel system shutdown -- Rich, 21:14:36 06/23/04 Wed