mpoo83

so to try to make this short, recently got a 2001.5 s4...the low oil pressure light keeps coming up...i replaced the oil level sensor, oil pressure sensor and oil pump...the light is still coming on..i hooked up a mechanical gauge where the sensor would go...there was almost no oil pressure at idle, and around 25ish at 2000rpm's...i'm lost on what this could be at this point..is there supposed to be a gasket between the oil pump and the block? also there is a metal tube that goes from the pump to the block. there are no o-rings on that also...any ideas..any help is appreciated..i'm out of ideas..thanks

Peter Badore

You should look in ETKA to see an illustration of the the oil tube o ring seals. There should be o rings on the the oil tubes.

evilEE

if you changed the sensor and checked the bottom of the oil pump to make sure the screen isn't clogged the o-rings are prob your problem. There is supposed to be a total of four, 2 o-rings for either side on each tube I believe.

I just looked at mine recently and I believe there are two tubs that need them.

mpoo83

hey guys, so i added the gaskets..started her up..let her idle for a short while and then took her for a drive...no alarms...it had to be too good to be true so i let it warm up a little more and took her for another drive...got the alarm again....i clicked the little button next to the display and the screen reads "turn off engine and check oil level"...the icon that blinks is like an oil pan thing with drips coming from it..and then that message...i also already replaced the oil level sensor too though...now i'm really confused...don't really hear any unusual noises from the motor either...

evilEE

I would now start checking electrical. I'm not absolutley sure I follow how your explaining the problem but it looks like you have a low oil warning or low oil pressure warning or both.

What gasket did you change? The oil pan gasket, or the o-rings on the metal tubs next to the oil pump?

The oil pressure line indication is looking for a ground from the oil pressure swtich. You can check the electrical by disconnecting teh oil pressure switch and jumping it to ground and the light should go off. If not, you have an open somewhere or your instrument cluster is hosed. Oil temp/level can be trouble shot the same way w/3 wires though.

mpoo83

on the center digital readout, the red oil light will show up with drips coming from it...from what i have read, this means low oil pressure...just below the tachometer, there is the clock with the button that changes the time and also changes the display for the center. when i push that button in, the center display now shows "turn engine off and check oil level" ..this part would make me think low oil level..so i am confused as well

for the second part, i have changed all the gaskets on the metal tubes next to the oil pump.

i'm going to try checking the wire tonight..one of my buddie's is friends with an audi mechanic, so hopefully he can come over and help trouble shoot....according to the audi guy, these are common problems..

mpoo83

my mistake...i meant to say i changed all of the o-rings on the metal tubes, not gaskets....

evilEE

ahhh... understand now.

I have the same problem and changed o-rings and checked screen on oil pump. No sludge to be found. Same light comes up. I jumped the wire to show the wiring and the indication (instrument panel) is working. I could run the motor and connect and disconnect the wire from ground and control the failure so I know my wiring and cluster are good. So, I ordered a sensor from ECS for 7 bucks. Gonna change the sensor, if that doesn't fix..... I'll change the last component which is the pump.

mpoo83

does anyone happen to know what kind of oil pressure these cars run? i've done some research and have found different things..i've found some people say 10psi at idle, and others 40psi..

i hooked up the mechanical gauge again...i'm seeing anywhere between 5-10psi at idle....around 30psi at 2000rpm..and 4000rpm i get around 50psi..i bought my sensor from the local audi dealership for $20, figured it wasn't too bad and i usually try to stay factory when it comes to sensors...is there a chance it was bad right out of the box?..i've had that happen with my jeep before

i have yet to check the wire, and that may or may not happen tonight...

DxC

ive dealt with my fair share of low oil pressure light issues ... and sometimes it is the flimsy wire that goes from the oil pressure sensor - other times its a dying motor.

first get out a multimeter and check continuity on the wire from the sensor to where it plugs into the harness

also u should be able to hear a knock develop if oil pressure really is that low. i think it should be 20psi pressure at idle, and like 40 once revved up

basically your main/rod bearings hold very tight tolerances to allow oil pressure to build up ... if the bearings become worn, even a little, the pressure goes down dramatically.

prob not what you wanted to hear, i know everytime i come across it i pray it is just a simple sensor, or wire, or pump ... but unfortunaely that isnt always the case.