pach21

Hi all, I am working on my first Audi, it is a 96 A4, I am not receiving any oil pressure to the left head. I know this because the oil pressure was tested by a mechanic on both sides. I can hear the lifters making noise only from the left side. I took off the valve cover and removed and inspected the pressure relief valve, no problem. I then worked my way down to the oil retention/check valves under the intake, removed and inspected, found what appears to be a little piece of gasket or hard plastic. In order to make sure the passage between the pressure relief valve and lower check valve I tried to blow air through with a compressor but only very little air makes it through, with the sound that somethings blocking passage. I did it to the right side and there is no obstruction at all. I really don't want to take the head off but will if I have to, just wondering if anyone else had something similar or has any ideas how to resolve this without taking off the head. When I took the valve covers off, the inside was filthy with residue. Thanks in advance for reading.

pach21

Also when I first started shooting air through the pressure relief valve port, no air at all was coming out from the check valve port. Only after a little while did a little air start making it through. I am fairly certain the blockage is in between. I was using the diagram on 12v.org for reference http://12v.org/engine/index.php?section=hw&sm=oil

CRAZY_RUSSIAN

sounds like the valve is capoot, replace it with a new valve and c what happens, but it dose sound like weard problem. also i would run seafoam thru the engine after you get this figured out.

pach21

I started injecting oil in the port and shooting it through both ways with compressed air, little by little it broke through but still not a clear passage. Going through the records, the last owner replaced the oil cooler gasket so I kinda think its junk or pieces of gasket that are stuck. I just bought seafoam, and will run it through once i get it put back together.

pach21

Also did a compression test before I started and everything check out okay

CRAZY_RUSSIAN

sounds like you know what your doing man:-)

pach21

thanks, well i tried running the car with the right side pressure relief valve plugged to see if oil got the the left head, and it did. The pressure was way too low though. My conclusion is a bad oil pump, anyone agree, disagree?

CRAZY_RUSSIAN

i would replace the check valves before doing the oil pump. also do couple flushes with seafoam first. how are you testing oil pressure in the heads? btw, check to make sure you are using a correct oil filter for your car/engine as there are 2 different filters that will bolt up to the car, but they have different releaf springs in them and provide different pressure

pach21

I took out and inspected all 4 of the check valves, they are all in good order, replacing them at $50 each seemed kind of steep to me. Doing the seafoam flushes to me seems risky because id have to rev the engine up, and the sound coming from the lifters is steadily getting worse. We had a mechanic test the pressure for us, sounds kind of bad but I dont have a report of psi, but I do know the left head is not getting any, I know this because I started the car with out the valve covers and oil would only come out the right side through the pressure relief valves. Even with the left side supposedly clogged, the pressure to the right was some what low. One thing I did find interesting was that the oil filter was the wrong one, I guess the previous owner put on a filter for the 1.8L engine instead. To me it seems like that wouldn't mess the pressure up because the 1.8L engine has higher oil pressure then the 2.8L. Still at a loss, I'm getting a used oil pump on Monday.

CRAZY_RUSSIAN

did you check the valves in your valley pan? (under intake?) those are the ones that usually cause problems