Hello all,

I have a 2004 A4 with 1.8T with 59K milesand I suddenly starting having low oil pressure warnings come on when coasting or deceling with RPMs in the 1700 - 2000 range. Took the car in, they measured the oil pressure and they said it is 10psi vs 18psi normal at idle and about 38psi at 3K RPMs. No sludge at all. They suspect the oil pump is going bad, but they don't really know.

Have any of you B6 1.8T owners had an issue with oil pumps failing or decreasing in performance at a relatively low car mileage? Seems strange to me that an oil pump, which is always fully lubricated, would be failing at such a low lifetime.

Thanks,

 

Was this an Audi dealer that checked it out, because the answer you got does not make much sense to me. Did they pull the pan? If not then how do they know the screen is not plugged? Oil pumps do not fail in that manner, they just quit, they are basically a set of gears, so they either pump or they don't. Oil pressure could be low if the engine is worn or if it is leaking past somewhere. I would want to see the pickup screen.

 

Thanks for the reply. Yep, took it to an Audi dealer, they pulled the pan expecting sludge and found a small amount on the screen. They cleaned it up, put a new pickup tube in, and put the pan back on, but still the same issue. I thought the same thing -- oil pumps either pump or not -- there is is no degraded performance. Looks like I may have something major going on.

Thanks,

 

I don't know, but I do not know that much about the engine internals, it would be nice to sit down with an Audi mechanic and brainstorm possible causes. It is unlikely the bearings are worn that much, I would think you would hearit knock if they were.

 

Alrighty, here is the latest. Oil pressure was 0psi at a hot idle. Tech found very little sludge in the pan or on the head, but changed the pickup tube and oil pump. After that, hot idle oil pressure was up to 12psi, but still under the 18psi idle spec.

However, the tech started looking through the service manual that recommended that he check the oil breather vacum tube that goes from the top of the engine, down the back, and connects to the oil filter housing. Apparently the vacum in this tube influences or controls an oil pressure bleed valve in that housing. The tech found my tube to be in very poor condition and not holding any vacum. After replacing the $90 tube, my hot idle pressure was up to 22psi, so all is well. Who would have though!

Thank you all for your suggestions and help.