Just got timing belt done last week on my b5 99.0 A4 (96000 miles), it has the 2.8 30V V6. Since then, i have had an intermittent warning light show for oil pressure being low on the screen in the middle of the cluster.

My mechanic has so far changed the oil pressure switch and done a full engine flush replacing the oil with fully synthetic mobil 1 5w30 and a bigger filter. Then on my trip home after the flush and oil change the light came on once again.

The mechanic was convinced that it was due to carbon deposits within the oil, which would have hopefully been removed by the flush, and he showed me the extent of the buildup on the oil cap on top of the engine, which had a 2/3mm layer of the stuff on it.

But now we are at a loss as to what the problem could be, has anyone experienced this sort of oil pressure issue before as it is very worrying. I think (and am hoping) it may be an electrical issue as it comes on at random times, but it may be something more and i fear my engine will be in trouble!!!

So, any ideas....
Thanks.

 

did he changed the oil pressure sensor? did he checked the connections and if he has a good ground?

 

If by oil pressure sensor you mean the oil pressure switch that screws in above the oil pan then yep, i have had a new one put in.
Which connections & where would i check for those though?