Warning Light

[102487thedude]

my car gave me a warning in the yellow warning box on the dash that said check oil sensor. so i replaced the oil level sensor and the oil pressure sennsor. Now the oil sensor light has gone off but know in the red warning box i have a flashing oil symbol have any ideas what it is.

[dirtybrd]

First off make sure you have oil pressure.

[102487thedude]

just found out that it is low oil pressure so what should i do to find the problem. please help

[absolutegtr]

The oil pickup screen may be clogged due to sludge buildup.

Either:

1) at night drain the oil and look up through the drain plug hole (with a flashlight) and see if there is excessive buildup of sludge on the pickup screen

2) Drop the oil pan and check the pick up screen

[102487thedude]

just drained the oil and no problems as far as sluge buildup on parts or on the screen.

[04A41.8TCVT]

Did you hook-up oil pressure sensor correctly? Was the oil pressure sensor new? Can you install the old oil pressure sensor? and see if the problem goes away. If the pressure is sensor is ok, then it maybe a sludge issue.

The sludge is really not the sludge that we all think of, it is the clogging of the oil pick-up screen on oil pump due to carbon / coke deposits. I am not sure if you can really see the pickup tube screen thru the oil drain hole or oil sensor hole unless you are using a borescope. To make sure that you have oil pressure, connect a cheap oil pressure gauge where the oil pressure sensor goes and check the pressure reading. I am sure somebody will chime-in for the correct oil pressure. Do not drive your car in this condition, you may damage the engine. You best bet is to drop the oil pan and replace the oil pick tube at the very minimum. What year is your A4 and how many miles? 2002 with over 80K miles?

[102487thedude]

It was a brand new block and motor with and have around 20,000 miles on this setup not even one year yet

[102487thedude]

what is stock oil pressure at idle peed on our cars

[dirtybrd]

Not sure, but you need approx 10-15 psi per every 1000rpm. Example 60psi @ 6000rpm.