1988 Audi 90 Quattro fuel problem
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1988 Audi 90 Quattro fuel problem
My 1988 Audi 90 Quattro is having some serious fuel problems. It all started when I was driving home and while stopped at a light, smelled a strong fuel smell. As it turned out, the rubber fuel hose beneath my car had cracked right by the clamp. I pulled off and replaced the hose, but my car still wouldn't start after that. I thought maybe the replacement hose was kinked too much because of the weird angle it turns, so I replaced it with a little bit longer hose and STILL no luck.
Then I cranked it a few times to see if maybe it just needed to work the air out of the line, but still no luck. At this point, I discovered that there is a little green unit bolted onto the side of the fuel distributor that was leaking fuel. It seems to be some kind of pressure release, but I'm not sure - it very well may just be broken. All I know is that whenever the fuel pump runs, it starts dripping.
Any thoughts on how to get this thing running?
Pardon my lack of automotive knowledge - I'm learning.
Then I cranked it a few times to see if maybe it just needed to work the air out of the line, but still no luck. At this point, I discovered that there is a little green unit bolted onto the side of the fuel distributor that was leaking fuel. It seems to be some kind of pressure release, but I'm not sure - it very well may just be broken. All I know is that whenever the fuel pump runs, it starts dripping.
Any thoughts on how to get this thing running?
Pardon my lack of automotive knowledge - I'm learning.
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From: CT
Did you mean little grey thing bolted to the side of the fuel distributor?
That would be the differential pressure regulator or DPR. It could be plugged up, it seals with some o-rings so you may just need some new o-rings. Be aware a new one is $$$ you may want to shop for a used one if you are considering replacing it.
That would be the differential pressure regulator or DPR. It could be plugged up, it seals with some o-rings so you may just need some new o-rings. Be aware a new one is $$$ you may want to shop for a used one if you are considering replacing it.
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I tried replacing the DPR with one from the same year and model at a U-Pull, but the car still won't start. Is there an easy way to identify if my replacement part is a dud?
If I leave the car sitting for awhile, it will fire once but then dies every time. Any thoughts?
If I leave the car sitting for awhile, it will fire once but then dies every time. Any thoughts?
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From: CT
Are you getting good spark? Using the correct spark plugs? Rest of the ign. system good cap, rotor, and wires? Then back to fuel leaking fuel injectors are possible. Could have a big vacuum leak or several.
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The cap, rotor, wires, and distributor have all been replaced in the last 2 years. It's hard to tell if fuel is leaking anywhere else. I don't smell fuel nor see it leaking anywhere else, but I will look more thoroughly. The plastic brackets that hold the braided steel hoses from the fuel distributor have been broken since I got the car, so perhaps something went wrong there. I don't know how essential they are, if at all.
I haven't checked for spark since this has all come to be a problem since I replaced the hose to the fuel pump that cracked (the hose, that is). It seems unlikely that a spark issue would arise at the same time. I'll check it out tomorrow and post back, though.
I haven't checked for spark since this has all come to be a problem since I replaced the hose to the fuel pump that cracked (the hose, that is). It seems unlikely that a spark issue would arise at the same time. I'll check it out tomorrow and post back, though.
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I can't recall if we had replaced the filter or not. I can hear the fuel pump priming consistently. It will run for about 4 seconds and shut off every time I turn the key on.