I floored my 2000 a4 z28 the other day. turned back on read low oil. changed the oil put in 5.5 quarts. pressure at idle was 40-50 psi, and when driving it would go to 80psi. now i floored it two days later, the oil pressure droped to 35 psi at idle and climbs from there, and temp is at 210degrees. is this normal, what seems to be going on?

 

oil doesn't read low. and is it safe to drive at that oil pressure?

thanks

 

Sounds OK to me. Sounds like it just got low and the light came on when it sloshed around a bit.

-Geoff

 

There's nothing wrong with 35psi hot idle. Heck I wouldn't even worry at 20psi hot idle as long as it climbed ~10psi per 1k rpm.

 

I wouldn't worry about it, just like everyone else said it's pretty normal.

 

well it went back to reading from 45 at idle climbing to 70. but when i get on the gas, the oil pressure goes back down to like 30 at idle and then climbs to 55. should i replace my oil pressure sending unit?

 

Did you not listen to what everyone told you? The pressure will change depending on the temperature, you don't have any issues and it's perfectly normal but you still want to fix something that's not broken? Should i change oil sending unit because i have 65psi at warm up idle then it drops down to 50psi when fully warmed up? (don't compare my numbers to yours, i have a ported oil pump)

 

My car when I don't go WOT idle is 45psi climbs to 75psi with rpms. My issue is when I go WOT, my oil pressure at idle afterward will be like 25-30psi and climb to 50-55psi. It never did that before, I am not comparing your numbers to mine, I am getting different numbers after WOT and was wondering if my sending unit was acting up or this is normal. It doesn't seem normal because it hasn't done this before

 

Could be your sending unit but the more likley culprit is the oil itself. After a hard WOT run your oil temp will increase causing the oil to thin and the pressure to drop a little but not usually that much.
What brand/weight oil do you have in it?

 

mobile 5000 mile 5w30

 

This thread makes me lol