924Board.org

[LeeXIX]

First, I want to thank you all for your help on that round ballast resistor.

But, I just want to double check on something I found in my Haynes about the fuel pump.

I'm the guy who has the car that runs for a few minutes and then the car quits. It restarts great but then runs for another minute and then quits again. I put in a new fuel pump relay but that did not fix the problem. I spoke to the guy who had the car before me and, after interrogating him for a half hour, found this:

He had the same problem-The fuel pump relay fuse was blown, so he replaced the fuse, he replace the fuel pump (only) and the problem still was not fixed. He put the old pump back on and that is how I got it. He started arguing with me about there being another pump in the tank. I told him that there was not.

Well, I pulled the sending unit and I was right (I have had a few VW Golfs that had two pumps so I had to make sure). I checked the pump with a voltmeter and found 11.89 volts to the pump (Haynes said that there should be at least 11.5) I then checked the pump with one connection on and my voltmeter inline with the other wire to the pump (like my Haynes said) and I found that I had 11.89 volts when checked that way. Haynes said that I should have no more than 8.5 volts. Is that right?
Also, I have been checking on a pump for my car (It's an early one) and the cheapest pump I have found is about 600.00 USD. can I use an later model pump on my car instead and have it work alright?
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I have a 924 (yellow) Porsche since I lost my 1971 914 in my divorce. She threw out everything except the shell of the body.

[Smoothie]

Model year?

If you have wires to the area of the tanks' fuel outlet, you have an in-tank pump, otherwise you don't.

By your description of the test you did "inline", I think you were supposed to be doing an amp test, not volts.
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"..it's made in Germany. You know the Germans always make good stuff."


'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

[LeeXIX]

You were right. I had forgotten to set the meter to amps. I rechecked it and the pump runs between 6.5 to 7.0 amps draw.
My car is an early model 77 924 2.0. I replaced the fuel pump relay with a new one. I cannot find anything else. I was told that after a few minutes the relay switches to the warmup regulator after running a few minutes but I cannot find that setup in my wiring diagrams.
Any clues as to where I might continue my searches?
I did a followup and ran the car until it quit and rechecked the fuel pump amperage and found that it was 7.5 and after a minute it went down to 7.31 amps draw. I even unhooked the sensor that is on the air flow meter (the one you are to unhook for the test) and tried running it. No change...it ran for two minutes and then quit.
I must admit that at this point carburation is starting to look like a good option.
But I know that the fuel injection system (when it is operating correctly) is great.

Any ideas would be appreciated.

Thanks
Lee
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I have a 924 (yellow) Porsche since I lost my 1971 914 in my divorce. She threw out everything except the shell of the body.

[falconboy]

when it cuts out does it do it straight away or does it die slowly?
After it cuts out does it start again straight away and if not how long does it take to start again?

[LeeXIX]

The car runs for about 5 seconds then the cars idle drops to maybe 200 rpm for 2 seconds and the it quits. Also, you notice a change in the fuel pump tone. It seems as if a relay trips. The change is that noticeable. If I try depressing the accelerator pedal ith quits as soon as I touch the pedal.
The car does restart right away and then the same thing over and over. It is kind of hard to move the car around to work on it that way.
I have tried checking the fuel pump amp draw at different times and the reading stays the same (between 7.35 tp 7.5 amps), so no matter what, the fuel pump draw is the same when cold or when the car quits. Also, the pump is very noisy I mean that while it is running you can hear it very clearly in the drivers seat.

I just met a gut who bought a '79 924 and while I was working on it with him I noticed that his fuel pump is very quiet. But there are many different things I noticed between his and my car anyway. Like a 5 speed, power doors and mirrors, and the fact that it runs for more than 5 seconds. So I was comparing his to mine, but since mine is an early 77 model there would be a few differences.
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I have a 924 (yellow) Porsche since I lost my 1971 914 in my divorce. She threw out everything except the shell of the body.