Audi Coupe 16v - Cuts out when warm

[MrRP]

Hi,

I'm posting on behalf of my father. He has a 95 (M-Reg) Audi Coupe 2.0 16v.

He currently has a problem where the car will start fine from cold, drive for about 5-10 mins then cut out, once the car has cut out it wont re-start untill cold.

I've checked the coil for spark - which there is, Unplugged the lambda, then the temp sensor and that didn't work. I've checked for fault codes using a vagcom style software and there was none. Also the fuel pump does prime.

Anyone have any idea what the problem could be?

Thanks in advance.

[niall4313]

Hi mate did you ever solve this problem? i have the exact same thing happening with my 8v coupe and its driving me soft, so far ive replaced distributor, leads, coil, temp sender, lambda, ecu,and fuel filter. Since replacing the filter the car now only lasts for about a minute before cutting out, which leads me to believe the answer may lie here somewhere, but im at a complete loss as to what to do next? ..anybody out there got any suggestions?

[MR.FUSION]

Get your car to a tuning centre for a diagnostic, the problem will be picked up straight away.

[niall4313]

Have done so already, nothing showing- hence my frustration!

[niall4313]

somebody must know something??

[MR.FUSION]

Did it actually cut out during diagnostic?

[niall4313]

Yes it always starts and runs perfectly for 10 minutes then slowly starts to break down and splutter until it cuts out completely, then it wont start again for at least an hour until the engine is completely cold and then it does the same again. so far ive replaced the coil, distributor, air filter, fuel filter, fuel pump relay, air intake pipe, cleaned all pipes out cleaned all sensors with electrical contact cleaner,and even replaced the ecu, fuel pump is working and maintaining full pressure. Someone suggested knock sensor? although im not sure what effect that would have on anything. Te car itself is immaculate with only 100k on it so im reluctant to give up on this.

also forgot to say ive replaced temp sensor and lambda

[80Coupe3A]

I had the same on my 8v which has just done over 100k, and it always happens on the same strectch of raod coming home from work, which is down hill and when i engage the clutch thats when problems araise especially when coming on to a round about and the steering is heavy and the brakes are squeshy. I put it down to bad breathing when cold, wheather the choke cut out to soon due to i was using mainly the gas as i was driving, so gave it a good service, and changed exhaust and has been fine since, Does it cut out if you leave it ten mins ticking over?

[MR.FUSION]

Sounds funny that it only does it after about 10 minutes or so, then slowly starts to break down.

Makes me think along the lines of a dodgy choke? you know how your engine idles higher from cold then starts to slow down as it reaches its peak operating temperature?

This sounds a lot like it's related.

[niall4313]

Ive replaced the ecu so that should have fixed any problems since its the ecu that controls the amount of choke etc, but it still behaves the same it happens after ten minutes at idle, if i were to try and drive the car giving it revs the problem would occur sooner since the car would warm sooner, so it just seems to start cutting out when it gets to a certain temperature, im tearing my hair out at the minute, there seems to be a never ending amount of possibilites and suggestions yet none have had any effect so far.