924Board.org

[TurnKey]

I just purchased a 1980 931 from my In-Laws. The car has been in the family for about 15 years or so. It was driven from their house to mine, about 1100 miles. It ran perfectly all the way home. I have driven it around town since without a problem. On Saturday I washed it at the local do-it-yourself carwash. It ran horrible on the way home because of the water that got under the hood. I waited a few hours to let it dry and it ran perfectly again.

Yesterday, I started it and drove to the gas station. After going inside for a minute and coming back out, the car would not start. It has an old "the ungo box" in it but i was told that it is not hooked up and has not been touched in years. After tinkering with the car for a few minutes it started up and ran great again.

Today, I went out and tried starting the car and it will not start. The starter cranks great but the car will not attempt to start. I messed with the "ungo box" again and still nothing. I checked the coil for spark and at the #1 plug wire. Good spark in both places.

Any Ideas what could have caused this problem all of a sudden?

Thank You
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The Porsche Noob

'80 931

[fiat22turbo]

You've verified spark and air.

Do you have fuel?
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Stefan
1979 924 Carrera GTS (clone-ish)
1988 944 Turbo S (Silver Rose)

[TurnKey]

I'm guessing not. What is the easiest way to check? I'm pretty new to all of this.
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The Porsche Noob

'80 931

[fiat22turbo]

Go click on the 924 Technical Section and the FAQ at the top of the page.

Then look around for a link to the Bosch CIS troubleshooting book.

There is also the 931 Resuscitation thread: http://www.924board.org/viewtopic.php?t=22724

My guess? You have a bad ground under the dashboard that is causing the fuel pump relay to not trigger or perhaps another connection issue with the fuel pump relay circuit or a failing fuel pump.
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Stefan
1979 924 Carrera GTS (clone-ish)
1988 944 Turbo S (Silver Rose)

[emoore924]

An easy way to check that everything else it ok is to get some ether starting fluid, give her a quick shot, and crank. If it starts, you've got a (lack of) fuel problem.

Check pump, fuse, relay, wiring...

[Smoothie]

One quick-easy item to check..
The overboost cutoff switch - check that its' wire is tightly attached.
(Front-center of the upper charge tube, a few inches to the left of the throttle.)
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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

[Grenadiers]

I had to google 'ungo box', now I'm in the know! Also, did the car sit for a long time? Maybe gas in tank varnished some, dirt back there might have moved to the fuel filter. Change that filter yet? Is it on correctly? Are the three drain tubes cleared of leaves and dirt? Maybe that middle one is plugged and water worked it's way onto the relay/fuse area? Check the cap/rotor for water?
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'83 944 Track car.
'88 924S Track car.
'89 944 Turbo
2004 Winnebago Vectra monster RV
2012 Jeep Wrangler
2014 Kia Soul
2001 Ford F350 powerstroke

[TurnKey]

Thanks for everyone's input. I am still working on the fix but have very limited time right now. I will try to remember to let you know what i find to be the cause of this annoyance.

Thank you
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The Porsche Noob

'80 931

[Carrera RSR]

[TurnKey]

Turned out to be the Fuel Pump Relay...New relay and it runs great again.. Thanks for the help
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The Porsche Noob

'80 931