A4_Power

Hi all,

I just picked up a 2002 A4 1.8t last week. The seller told me that I would need to dump some money into it for it to run 100%. Here is a list of what I think needs to be fixed. I would like to know how much money I'm looking at to fix it up.

1) Plate light message. Yellow symbol of the lightbulb with an x. The seller provided me with the bulbs.
2) Oil sensor message. Yellow symbol of an oil can. I'm sure it's the oil temp as I read that the oil pressure is a red symbol.
3) Malfunction Indicator Light. Got it scanned at Partsource and they it was a P0420 code (Catalyst System Efficiency Below Threshold Bank 1). The car passed emissions with flying colours when I registered the car so I'm guessing it might be a faulty 02 sensor somewhere.
4) Humming sound coming from the exhaust area. I've read that this sound is a result of a clogged up fuel filter.
5) Everytime I change gears, the rpm gauge revs up about 500rpm before the clutch grabs onto the flywheel. I know this one is a big job.
6) Everytime I start the engine on a cold start, it sounds like it is revving high for about a minute and then it sounds normal. Is this normal on turbo cars? I've never owned a turbo car. I've also read that it might be a fuel pump issue.

Any help would be greatly appreciated.

Cheers,

Jay

Sly_North

1) change the 2 license plate bulbs, easy: one screw for each, pull the plastic holder, replace the bulb.
2) Oil sensor light = oil sensor dead (hopefully, happened to me too), or oil sludge (which will damage badly the engine). Get it checked/fixed asap.

5) Clutch to replace?
6) if by high you mean ~1200rpm, then after 1 minute getting down to 800rpm, that's normal. That's the to lubricate the engine and the turbo with oil, after the oil felt at the bottom of the engine in the pan.

A4_Power

Thanks for the reply. I've read about the oil sludge problem on these cars. The car I bought has 266,000kms but the engine was replaced at 140,000kms from Audi Canada because the oil sludge problem blew the original motor. So I'm guessing that with the new motor which now has 126,000kms, it wouldn't have the oil sludge problem. I've also read that the oil sludge problem produces a oil pressure warning which is different then the oil sensor warning.

a4audi4fun

Ref 5) RPM jump - does your cruise control work?

Could just be a faulty clutch switch; the hanging revs was the symptom for my clutch switch problem. If cruise doesn't work that is another symptom of a faulty clutch switch.