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 Post subject: 1982 944 ECU fault.Engine dies on start up.
PostPosted: Wed Feb 22, 2012 8:18 pm 
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Just wanting to share my experience. Having had my 944 for last 14 years - v reliable etc, I had the following symptom "from cold engine cranks and starts as per normal, finds idle as per normal for around 5 seconds, then loses its idle reference. Engine starts to hunt, tacho needle fluctuates from 1,000rpm to 500 ish. Engine runs a few more seconds as if on 2 cylinders, then dies. Only to restart OK and repeat the above". No amount of careful coaxing on the accelerator will get the engine to run well.It can be made to rev to around 3000rpm on the tacho, but engine is v unhappy and seems to run on 3 or even 2 cylinders. The cause of this sympton turns out to be the ECU, which has (I am informed) corrosion of the PCB's (both of them apparently). Am having the ECU repaired and hope to have back in the car in next 10 days or so. Am hoping that this brings this matter to a happy conclusion.


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 Post subject: Re: 1982 944 ECU fault.Engine dies on start up.
PostPosted: Wed Feb 22, 2012 8:48 pm 
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Needs more info. One thing that comes to mind is a loose rotor arm on the shaft, this can give weird symptoms. Throttle Position Switch, Air Flow Meter need checking & the flywheel sensors would be next on the list. Will it restart immediately once it has cut out. A dodgy earth could cause random injector faults as well.

This needs diagnosis with a planned attack rather than random changing of bits.

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 Post subject: Re: 1982 944 ECU fault.Engine dies on start up.
PostPosted: Wed Feb 22, 2012 9:38 pm 
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Thanks for the interest Jim. If my repaired ECU fails to cure the symptom I will investigate further. I know I have strong sparks at spark plugs and the injectors are firing ok. I have a good earth (strap contact is good), but I will look at throttle potentiometer, air flow sensor and crank pick up in that order. Other than substitution I am not able to diagnose. These old cars dont have any on board diagnostics (I think). Do you know the method for checking the potentiometer?


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 Post subject: Re: 1982 944 ECU fault.Engine dies on start up.
PostPosted: Sun May 06, 2012 8:35 pm 
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HI THERE, I HAD THIS SORT OF FAULT WITH MY 1982 944. IT TURNED OUT TO BE Air Flow Meter. WITH A QUICK LOOK ON UTUBE, IT WAS A EASY FIX. HOPE THIS MAY HELP.


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 Post subject: Re: 1982 944 ECU fault.Engine dies on start up.
PostPosted: Mon May 07, 2012 1:06 pm 
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Very common problem if the airflow meter is dead, not connected or has a break in its wiring.

For the first couple of seconds during cranking and startup the ecu software ignores the airflow meter.

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 Post subject: Re: 1982 944 ECU fault.Engine dies on start up.
PostPosted: Thu May 10, 2012 5:35 pm 
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Are you sure its an electrical fault & not fuel related ? dodgy pump, filter, fuel lines etc ? good luck anyway & let us know what it turns out to be please, Jinxy

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