90 V8Q Fuel and Oil Pressure Issues

[CA_V8Q]

Hi all!

I am a newbie to Audis and to this forum. I have a couple of issues that am hoping to find the solution to. I have owned a 1990 V8 Q for about 4 mnths now (169,000 mi currently).

1) Erratic fuel guage – About 2 weeks ago I got a new fuel filter put in. In the past week or so, I've noticed my fuel guage has been acting erratic. This is always when I first start up. Sometimes, I'll turn the key and the guage will show zero fuel (with warning buzzer sound from dash). Sometimes 1/4 full and other times 3/4 full. It goes away (i.e come back to normal) if I turn the car off and turn it back on about the 4th or 5th time. Is the problem a simple relay switch or worse, the fuel pump (yikes).

2) Oil pressure guage – Just last night I noticed the oil pressure guage doing the same thing – acting erratic. The oil was changed about 1500 miles ago. I have also noticed a small oil leak around the gasket/drain plug. Could this leak be attributed to the erratic reading of my oil pressure guage.

Could anyone help by telling me how serious each of these problems are?

Also how can I fix the oil leak?

[Harvey Smith]

I don't think any of your problems are serious. If it starts and runs OK the fuel Pump is good. I dont have the service manual for your vehicle so can't say exactly where to look for unstable fuel gauge and oil pressure gauges. For peace of mind you might test with an external oil pressure gauge to make sure it's OK. My experience is that Audi has some problems with sensors. The oil pressure sensor is screwed into the engine block and the fuel sensor is likely in the gas tank. These are quite easy to check in the shop and it shouldn't cost much to do so. Your oil drain plug may just need a tweak but don't overdo it. It might also need a new washer if that doesn't work.

[CA_V8Q]

THat makes me feel a lot better. SHall get it checked out and keep you posted. Thanks a bunch.

Clyde

[btobsharpe]

Electronics will sometimes act weird if the alternator is going. Every Audi I have ever had (and I've had 7 with high miles) has eventually had some weird electronic issue that is not related to the mechanical parts of the car.