Reject86

Hi there first post to this forum but have owned audis for years, Let me get on with describing the problem.

I'm Jamie I have recently bought a S8 d2 4.2 2000, took the car to the petrol station after it had not been used in around a month. Filled the car with roughly 10 litres to take the petrol light off as I wasn't going far. Drove roughly 3 mile with no problem, got out of the car but left the engine running. After about 5 minutes got back in the car and drove all of a mile before it started to act up, car Rev'd up roughly but had no drive (auto gearbox) and then started to run really rough. It lasted for around a minute then cut out, my petrol guage read 1/4 of a tank at this time. I tried to restart the car 3 more times, got the engine running but would not Rev with accelerator. So I got out, ran to a local garage who loaned me a battery booster and 5 litres of petrol, this took me about 20 minutes so gave the engine time to cool. Petrol in and guage went up further, car started on first crank and was not rough. I managed to get the car back to my home but the oil pressure warning was on the screen.

I honestly don't think it was lack of fuel due to the reading on the guage and 15 litres for 8 miles max of driving, I don't have a fault code reader but will be investing in one over the weekend. I had also noticed the low level oil warning but the car has plenty of oil in checked on the dip stick (cold and warm)

Any one have any ideas what could be the culprit? Any help greatly received. Thanks in advance. Jamie

123quattro

Water in the gas?

Reject86

It's possible, we have had a cold winter in the UK, to be honest I have never experienced water in gas on any previous car so wouldn't know what the effects are.

2001 S8

Sounds familiar.

When I purchased my S8 I had the same issue. Before I took ownership, the S8 had been driven roughly 50 miles in 4 months. When I drove it for the fist time she ran rough; almost like the torque convert was shuttering and there was no power. The gas tank was almost empty so I went to a gas station and filled it up with Premium (91 octane). She has ran smooth ever since.

I did have my mechanic do a scan of the transmission and everything looked good. So I chalked it up to not being driven and low or poor quality gas.

As for the oil pressure light, I have no guess.

Good luck.

123quattro

I could see all sorts of lights coming on when the engine is running below intended idle speed. The alternator probably isn't charging at that speed and controllers will drop off the bus at low voltage setting lights. Fix the idle, and I bet the lights will clear up as well.

twentysevenlitres

These suction jet pump feed lines for the fuel pump on D2's can behave funny. It wouldn't be a common occurrence, but when it's low I reckon it's possible for all the fuel to end up on one side of the tank and half the system may end up sucking air.
Especially if it's kept low, as a small amount of additional fuel will most likely end up in the right hand side of the tank due to the location of the fuel pump feed bowl which the filler neck is directed to.
It just so happens that that's the side the level sender is on too! - however the low fuel warning sensor is on the left hand side, so you should get a low fuel warning if this were to happen.

Anything below a 1/4 tank on these cars and you effectively have two tanks, I'd recommend putting at least a half tank in whenever you go to a petrol station, then your fuel is over the level of the saddle and both sides must be even. Then you should be able to run it near empty provided you fill it above 1/2 again next time.
I would never run one of these around with a continuously low level in the tank.

The fault may be erroneous (though I would never treat a low pressure oil light with indifference). I've been having battery issues with mine, and when I lose charge and canjust get it started, it nearly always throws a fault - usually ABS and Traction.

Joe_Beans

Hi I too have an S8, just been given it free.... Its a 2002 auto box, 360 horses jobby, I went to see it yesterday where it's been standing for the last 24+ months it started fine on jump leads and ran for ten or so minutes on idle, it was a little lumpy. I reversed it ten feet or so and realised the tyres were flat so I turned her off went and collected a compressor pumped them back up started again but really lumpy then died in a fit of splutters I'm guessing though its probably to do with the old fuel..... Will go put some fresh in there today and see how that goes!

Road King

I just went through this issue with my '02 S8. It started, but didn't want to idle. Next day ran fine. A week later, turns over but no start.

Turns out it was the fuel pump..it died at 119K miles. Car's fixed and is running well again.