help, she's dead
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help, she's dead
just filled it up 2 days ago with gas. driving home yesterday the check engine light came on and started giving me surging symptoms like when the idle switch was bad. just as i got home the light went out and started running fine. tonight i started it and got 2 miles down the road before all hell broke loose. it was popping and surging so i pulled over. it stalled as soon as i stopped. it restarted but i noticed the tach is moving all over the place. its running like it has bad gas and also smells like bad fuel. i was able to limp home by pulling over and letting it run for a while then going when it clears up. this is what leads me to believe its bad gas but here's the weird part. the fuel pump never shuts off with the key on, engine off. also there is a delay to engage the fuel pump when to key is turned on. also the low speed fan wouldnt shut off until i cycled the key again. the car is an 88 5000s. any ideas would be appreciated. gonna pump some fuel out tomorrow and see whats in it but the electrical part is what's worrying me. also, pulled a code for the light and it was the knock sensor. the wiring is pretty bad so i unplugged it hoping it would run better to get me home but no change.
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I had similar intermittent surging problms with my '875Ks, it was the differential pressure regulator, I replaced it with new one after several used ones exhibited similar but different symptoms, including cold starting problems. I was able to limp home after disconnecting DPR, one time this did not work & I was stranded, as I was close to home I had a friend tow me to my driveway which was icy & he couldn't tow up it, I walked to my garage, got one of the used DPR's, installed it & started & ran , ordered new one that night, many driveability problems went away with installatoin of new DPR
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still no good. filled it with good fuel. ran fine for 5 minutes then runs like crap. the fuel pump definitely never shuts off with key on engine off. i hope the pump isn't bad now. or the relay. any ideas? also my neighbor runs the gas station down the street. he saw and smelled the fuel and said that is smells like it is full of ethanol. said he never saw anything like that.
Last edited by one5k; Feb 27, 2011 at 03:17 PM.
Thread Starter
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[QUOTE=dkarten;24110745]the DPR is bolted to the front of the fuel distributor behind the pass. side headlight[/
i just noticed 2 weeks ago it was starting to leak so i ordered 2 seals for it but didnt put them in. it looks like its an internal leak tho so i probably need a new one. any idea why my fuel pump doesn't shut off with the key on engine off? normally it runs for 3 seconds then stops.
i just noticed 2 weeks ago it was starting to leak so i ordered 2 seals for it but didnt put them in. it looks like its an internal leak tho so i probably need a new one. any idea why my fuel pump doesn't shut off with the key on engine off? normally it runs for 3 seconds then stops.
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Is it possible the fuel pump is bad?
This guy has a lot of info regarding the ur-quattro, but much of the basic info is pertinent to a number of models
http://www.isham-research.co.uk/quattro/fuel_pump.html
This guy has a lot of info regarding the ur-quattro, but much of the basic info is pertinent to a number of models
http://www.isham-research.co.uk/quattro/fuel_pump.html
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Thread Starter
Audiworld Junior Member
Joined: Mar 2008
Posts: 87
Likes: 0
Is it possible the fuel pump is bad?
This guy has a lot of info regarding the ur-quattro, but much of the basic info is pertinent to a number of models
http://www.isham-research.co.uk/quattro/fuel_pump.html
This guy has a lot of info regarding the ur-quattro, but much of the basic info is pertinent to a number of models
http://www.isham-research.co.uk/quattro/fuel_pump.html
AudiWorld Member
Joined: May 2008
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From: Zinzinnati, Ohio
After you siphoned the gas out of the tank, did you also replace the Fuel Filter ?
If your fuel filter has sludge in it, the sludge will subside once you turn off the engine due to the lower fuel pressure. When you start it later, the car will run ok until the sludge builds back up at the filter exit line and causes the car to run like crap.
Also your Fuel Pump Relay, or its wiring, may be bad, as it is not cutting off the fuel pump after the 3 seconds. This would cause a "flooding" effect if the ignition switch is left in the run position for an extended time.
Considering the gas in the filter looked so bad, I would put some Techron in the tank to clean the injectors. Use Shell 90+ octane gas or better.
Since the fuel pump is running, I would think its still good. Sometimes the Ol'Skool guys know what they're talking about! I have heard of the mat liner of the fuel tank getting loose and being sucked up by the fuel pump, also causing problems.
First i would try the above, and change the DPR, before dealing with the messy fuel pump swap.
If your fuel filter has sludge in it, the sludge will subside once you turn off the engine due to the lower fuel pressure. When you start it later, the car will run ok until the sludge builds back up at the filter exit line and causes the car to run like crap.
Also your Fuel Pump Relay, or its wiring, may be bad, as it is not cutting off the fuel pump after the 3 seconds. This would cause a "flooding" effect if the ignition switch is left in the run position for an extended time.
Considering the gas in the filter looked so bad, I would put some Techron in the tank to clean the injectors. Use Shell 90+ octane gas or better.
Since the fuel pump is running, I would think its still good. Sometimes the Ol'Skool guys know what they're talking about! I have heard of the mat liner of the fuel tank getting loose and being sucked up by the fuel pump, also causing problems.
First i would try the above, and change the DPR, before dealing with the messy fuel pump swap.