Fuel to engine problem Audi 80 Sport 84'

80sport_owner · 02-03-10, 06:23 PM

Hello,
I am experiencing problems with my Audi 80 sport (1984)
Recently my car has been stalling due to what seems to be a lack of fuel getting to the engine. I have tried changing the fuel filter and clearing out some of the crap that's in the plastic reservoir near the electronic fuel pump. (sorry about my lack of knowledge coming out in my writing)

Basically what happens is: I turn the ignition over and can hear the pump working and the relay ticks twice indicating it seems to be working. I will then be driving along and the fuel pump starts making a loud struggling noise then i start to feel the engine stalling with lack of fuel.

Any ideas to answer my probably dumb ass question?

Thanks,
Mark

missfire · 02-03-10, 10:25 PM

get a new fuel pump....................

Hanuman · 02-03-10, 11:09 PM

Does the car run normally for the rest of the time? How long before the symptoms occur after starting?

It could be you are pulling bits of debris from the tank. Have you checked the filters again?

Fuel flow test. Fuel injection pumps for K-jet (I'm going to feel really daft if it isn't K-jet, or even injection) should deliver about 4ltr/min, as measured on the return to the fuel tank. And about 5bar pressure.

There's been some discussion over on the other channel- http://www.quattroforum.com/forum/wr...ving-fuel.html

and here, for the ur, but the basics can be applied to all similar era machinery
http://www.isham-research.co.uk/quattro/fuel_pump.html

Coxy · 02-03-10, 11:09 PM

a new fuel pump would be my first port of call.

Sounds like it could be on the way out. I had similar symptoms with my old coupe a few years go.
Word of advice, Audi can get them but go to GSF as they were less than half the price of what the main dealer quoted and had them in stock.

BIGGYIN · 02-03-10, 11:17 PM

Does it have 2 filters,like mine?Small plastic(gravity)one,then a larger metal canister one nearer pump?

missfire · 02-03-10, 11:20 PM

try running it with the fuel cap off..............?? blocked tank vent

80sport_owner · 02-03-10, 11:29 PM

Quote:

Originally Posted by BIGGYIN

Does it have 2 filters,like mine?Small plastic(gravity)one,then a larger metal canister one nearer pump?

Yeah it has the 2 filters. Ill try having the cap off for a while. I just didnt want to go spending money on pumps if it is still working. (student budget)

What happens is ill be driving for about 500 yards then it will stall but fuel pump seems to be struggling. Perhaps there is still shit in the tank.

It then starts fine, so im driving along and having to coast for a bit while i turn the key to pump some more fuel in. It then seems to last as long as that small amount of fuel lasts. And yes it is K-Jet and my 'car expert mate' knows sod all about really.

Ta for replies kind people

Coxy · 02-03-10, 11:31 PM

how noisy is the fuel pump???????

Hanuman · 02-03-10, 11:42 PM

I got the impression that this was happening infrequently. But with it happening so quickly, I'm inclined to think that the fuel pump is a likely culprit.

But. I'm not a fan of replacing things until some work has been done to identify exactly whats happening.

as mentioned earlier

-4ltr/min roughly, checked at the return line.
-5bar pressure minimum, with the system connected normally
-5-8 amps running current, and the pump really does need 12v to work well (there is a relay mod which has been carried out on ur's a lot)
-Fuel pump relays can be at issue, occasionally. Bridging the relay contacts so the pump runs continuously is worth a go. ONLY for test purposes, to identify the problem. If that works, then a new relay. Don't be tempted to run that permanently.
-check the filters again, see if they are full of crap, again. How much did you remove last time?

nickt241 · 02-03-10, 11:41 PM

check the earth for the pump,chances are it will be corroded and giving an intermittant connection,you can test this by linking in a temporary earth on the negative terminal on pump then driving car to see if symptoms persist,while you are there make sure both positive and negative terminals on pump are secure...if this dosent sort it then change the relay(easy and cheap)also check connections on plug to relay and give them a blast of WD,relays can break down over time as they only contain a wire coil and a set of duel points similar to ignition points........if neither of these virtually free repairs cure it then it will be the pump cos theres nothing left....its doubtful to be tank debris but even if it is then it renders the pump U/S

02-03-10, 11:09 PM	#3
Hanuman Trickster Classic Audi Club Member Join Date: May 2009 Location: Heckling from the cheap seats, Phnom Penh, KoW Posts: 7,021	Does the car run normally for the rest of the time? How long before the symptoms occur after starting? It could be you are pulling bits of debris from the tank. Have you checked the filters again? Fuel flow test. Fuel injection pumps for K-jet (I'm going to feel really daft if it isn't K-jet, or even injection) should deliver about 4ltr/min, as measured on the return to the fuel tank. And about 5bar pressure. There's been some discussion over on the other channel- http://www.quattroforum.com/forum/wr...ving-fuel.html and here, for the ur, but the basics can be applied to all similar era machinery http://www.isham-research.co.uk/quattro/fuel_pump.html __________________ I wish they would keep the damned Chinese away now that I can go home, so that I can enjoy Fish amok and a draught Angkor

02-03-10, 11:42 PM	#9
Hanuman Trickster Classic Audi Club Member Join Date: May 2009 Location: Heckling from the cheap seats, Phnom Penh, KoW Posts: 7,021	I got the impression that this was happening infrequently. But with it happening so quickly, I'm inclined to think that the fuel pump is a likely culprit. But. I'm not a fan of replacing things until some work has been done to identify exactly whats happening. as mentioned earlier -4ltr/min roughly, checked at the return line. -5bar pressure minimum, with the system connected normally -5-8 amps running current, and the pump really does need 12v to work well (there is a relay mod which has been carried out on ur's a lot) -Fuel pump relays can be at issue, occasionally. Bridging the relay contacts so the pump runs continuously is worth a go. ONLY for test purposes, to identify the problem. If that works, then a new relay. Don't be tempted to run that permanently. -check the filters again, see if they are full of crap, again. How much did you remove last time? __________________ I wish they would keep the damned Chinese away now that I can go home, so that I can enjoy Fish amok and a draught Angkor

02-03-10, 10:25 PM	#2
missfire making wooden things Classic Audi Club Member Join Date: Dec 2009 Location: cow land Posts: 8,156	get a new fuel pump....................

02-03-10, 11:09 PM	#4
Coxy 4 Ring Mafia Classic Audi Club Member Join Date: Jul 2007 Location: on the side of a hill in Shropshire! Posts: 28,215	a new fuel pump would be my first port of call. Sounds like it could be on the way out. I had similar symptoms with my old coupe a few years go. Word of advice, Audi can get them but go to GSF as they were less than half the price of what the main dealer quoted and had them in stock.

02-03-10, 11:17 PM	#5
BIGGYIN 4 ring whore! Classic Audi Club Member Join Date: Mar 2009 Location: Merseyside Posts: 7,976	Does it have 2 filters,like mine?Small plastic(gravity)one,then a larger metal canister one nearer pump?

02-03-10, 11:20 PM	#6
missfire making wooden things Classic Audi Club Member Join Date: Dec 2009 Location: cow land Posts: 8,156	try running it with the fuel cap off..............?? blocked tank vent

02-03-10, 11:31 PM	#8
Coxy 4 Ring Mafia Classic Audi Club Member Join Date: Jul 2007 Location: on the side of a hill in Shropshire! Posts: 28,215	how noisy is the fuel pump???????

02-03-10, 11:41 PM	#10
nickt241 Grown up member Join Date: Feb 2010 Posts: 132	check the earth for the pump,chances are it will be corroded and giving an intermittant connection,you can test this by linking in a temporary earth on the negative terminal on pump then driving car to see if symptoms persist,while you are there make sure both positive and negative terminals on pump are secure...if this dosent sort it then change the relay(easy and cheap)also check connections on plug to relay and give them a blast of WD,relays can break down over time as they only contain a wire coil and a set of duel points similar to ignition points........if neither of these virtually free repairs cure it then it will be the pump cos theres nothing left....its doubtful to be tank debris but even if it is then it renders the pump U/S