Red oil pressure warning came on
Asked by Zanman5000 Dec 01, 2015 at 12:02 AM about the 2005 Audi S4 quattro Sedan AWD
Question type: Maintenance & Repair
Red oil pressure warning came on. The status of how it is driving has not
changed. There is no knocking or pinging. I checked the oil, it was a little low
so i put a quart of full synthetic premium oil in. Problem still persists.
6 Answers
That light is on for a serious reason. Full quantity does not mean full oil pressure. For the sake of a $3,000 engine, have it towed to a shop or dealer. The sending unit may be faulty, giving a false low read. (Hopefully that's all) But that is a $10 part and the engine needs to be checked with a diagnostic computer, and I don't mean OBDII. But also, you say "a little low" and you added a full quart? Overfilling is just as bad as low, the crankshaft can dip in to the oil in the pan and whip it in to a foam...like a blender, causing no oil pressure
Zanman5000 answered 8 years ago
The oil is exactly the amount it should be after that quart. And i am aware that putting too much oil in can be harmful. I am a mechanic, i worked at Nissan for 3 years, but this is my first Audi, and in my opinion i dont know that much about it yet. Im letting her rest for the night. Although, If there were no oil pressure im sure i would know the difference in how she drives. Wouldnt u think?
With no tapping/knocking sound I do not think it would effect performance. But an Audi is not so exotic to be different than any car as far as that's concerned. I still lean to faulty sender. I did not mean to insult you as if you know nothing about this stuff... I have a bad habit of doing that.... going under the assumption that a question is from somebody that knows jack.
Zanman5000 answered 8 years ago
Im confused, r u calling me the sender, because i asked the question? I know plenty about cars, especially Nissans cuz i used to get paid o work on them. But like i said this is my first Audi. And really what im trying to ask is if this issue is something i can fix myself through trouble shooting a few things or should i immediately take it to my Audi guy?
No, no, I mean oil pressure sending unit. No way would I call you a faulty sender.. as a person. In the early 90's I had a Quattro that one day my (then) 6 year year old decided to fill her up... with the garden hose. The the wife pulled the hose out and proceeded to drive away. She got about one block and called me, bitching about 'her' car died. I don't know about the Audi's these days, but this was a 2.5L 5 cylinder that had a 'fuel distributor' that ran off camshaft, and produced something like 2500 psi (no typo, 2500) fuel pressure, it was set up to inject a such a moment to overcome compression and that little 5-banger would scoot. I think it was about 250 HP. Anyway, the car, after $1500 work, was never the same. Since you asked, my opinion is take it you your Audi guy. When I said they are not exotic... well maybe I jumped the gun. Audi's are fairly exotic and what you spend may well save you a lot more in the end game.
I went back and looked it up and it was a 2.2 with 210HP. Still pretty decent
