Where is the oil filter on a 2005 Audi A4, 2.0 liter, Quattro?

Check for a leaking valve cover gasket/s .

My 2005 A4 3.0 convertible audi is not a diesel, but I had a similar experience with a low oil signal going on and after checking the oil, which was sufficient, and replacing the dipstick, the light did not come back on until a subsequent trip. The light usualIy went on when I was close to the needing an oil change. I've had the car, a used one, for about two years, and the oil light minimum signal started behaving like yours early. About a week ago the oil pressure warning light came on. I don't know if there's a relationship, but if there is be careful. Audis of our vintage have a problem with sludge build up that damages the oil pump, which is a costly item. If you drive the car with low oil pressure you may seriously/fatally damage the car. I don't know if the sludge, if that's what you have, can be cleaned out, but I'd do it if it can be. My mechanic advised me to trade the car to a dealer rather than fix it. Hope you have better luck!

it doesn't matter what brand you use, just make sure you use the motor weight on the cap (don't use Pennzoil)

The insert or cartridge filters are easy to change..You must jack up the front of the car, remove the engine belly pan. in the front of the motor there is a black cylindrical housing for the oil filter cartridge..On the bottom is a cap that just screws off..Unscrew the cap, take it off, slide the old insert off, then slide the new one on..Screw the cap back on and voila! you are finished..If the insert came with a new rubber o-ring, make sure to replace the old one on the cap.

cannister...easy as pie...you'll need to get under the car using ramps and/or jack and jack stands.

YOUR OIL PRESSURE SWITCH IS DEFECTIVE

use a factory filter ( if not avail use Fram brand) and any name brand 10W-30W oil.

Check out these 2 websites, eautorepair and alldata, you register your car and pay for access to manual info for a time period u set (eautorepair 1week to 1 year, $11.99- $29.99, u can print any info off your computer). Let me know if u can't find your vehicles info.