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rg-series · Joined: 25 Feb 2006 Posts: 17 Location: Tempe, Arizona USA

I recently purchased an 80 931, that runs but has some issues. It is very slow and at about 2500 RPM the engine mis fires. In neutral it revs up past 3500 withough any problem. at 2500 RPM I was at 5 lbs of boost. Does this sound like timing or fuel delivery?

Khal · Posted: Tue Feb 28, 2006 5:11 pm Post subject:

I can't really help too much, unfortunately.

But running up to 5psi at 2500rpm doesn't sound right to me

Sounds far too early... an overboost problem, perhaps?

Makes some sort of sense then that you can rev it up in neutral... there'd be no load on the engine so the turbo wouldn't spool up.

Of course, it could also be either timing or fuel delivery problems as well.
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'80 924 Turbo

rg-series · Joined: 25 Feb 2006 Posts: 17 Location: Tempe, Arizona USA

alright thanks, I'll check it out to see if it's a boost problem too. I noticed on my block a "3013" number and according to a reference guide that is the code used for the 177 HP non US model. Could someone have swapped motors and that is why it spools up quicker?

Khal · Posted: Wed Mar 01, 2006 12:18 am Post subject:

Smoothie · Posted: Wed Mar 01, 2006 2:44 am Post subject:

You'll have 2 "charge tubes" bolted together that connect the turbo outlet to the intake manifold. Grab the tube

over near the windshield washer reservoir, push down and pull up on it. It should feel solidly attached to the engine. If not, the turbo to lower charge tube connection is being pushed apart as boost builds. This happens when the bracket that's supposed to hold the lower charge tube to the front of the block becomes disconnected. That normally happens as over time, one of its' bolts loosens, then vibration gradually cuts the bolt in half. If this is the problem, it's good to combine the repair with a timing belt and tensioner replacement and/or water pump replacement.

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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

Paul · Posted: Wed Mar 01, 2006 10:00 am Post subject:

Also check to make sure you have a nice blue spark. If so then check the plugs and wires.
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