When my car starts up oil psi is fine..but after about 15 to 20 mins of driving oil pressure drops to right above zero. I have full oil. It's been doing it for a while, I just want to tackle it before it messes something up. I believe that's what's messing up my idle rpms. Air Pump? Oil Pump?

 

the oil pressure gauge is notoriously inadequate and inaccurate. You might want to clean the connections to the pressure sender. Its located underneath your oil filter... its just a one spade connector .. clean it out with some good **** and put some dielectrice jelly on the connections.. should help.



My gauge doesn't work at all... dunno why.. new sender, cleaned up wires... just hasn't worked since my rebuild. To fix your oil pump you would need to remove the MOP and front cover... something you really only do when you are doing a rebulid... (ie its not the problem) if your car wasn't making any oil pressure.. it would have blown up by now.



The air pump has nothing to do with your oil pressure.. it does however have VERY little to do with your idle.. i'd remove it. Its just for emissions to keep the cat hot during idle...

 

Well it does make pressure and the gauge seems to work. I have an automatic and when the car is cold it makes good oil pressure and the idle is fine in gear. But when the car is warm the oil pressure reads like 10psi and the idle is like 500 in gear with brakes pressed and 500-600 without brakes. But in neutral it idles at a smooth 800. The oil pressure does rise when I accelerate, not to any extreme levels like 120 or anything more like 70 or so.

When the car is cold every gear idles at 800.



I have no idea what this problem is...it's been going on for a while so I guess it's not the oil pump.

But the gauge is not broken and it reads quite well. I'm not sure what the hell I should do and don't have the money right now to do jack anyways.



On the other hand the trans is still in good shape, oil level is full.

I've tried all kinds of oil to fix the problem.... vr1 20w-50, royal purple 20w-50, mobil 1 10w-30, list goes on.



I'm not too mechanically inclined... I grew up in the suburbs and my parents just put their cars in the shop to get them fixed. Hell I'm still trying to get a good tool collection. So I'm learning a new thing everyday.



The engine only has 98000-73000= 25000 miles on it.

 

Sounds normal. The guage will usually read nothing at idle. The thing about your idle dying during braking just sounds about normal. It would probably have something to do with the fact that your engine is pulling vacuum for the brake booster. I wouldn't be too worried about it. As long as its not stalling. When you are sitting and you apply the brakes it goes to 500rpm? And when you let off the brakes it idles up at 800rpm?



I wouldnt' be too worried about it. Sounds normal.

 

I had the same problem last week. After replacing the oil pressure sending unit, the pressure was at about 30 psi at idle.

 

yea... it seems normal... it just gets on my nerves whenever the car idles at 500 cause it sounds like it's not hardly even running.

How much was that oil pressure sending unit?

 

$69 from the dealer.

 

change the oil. when the oil gets to its last legs, and has seen about 2000-3000 miles, you will notice the pressure get lower, as the oil breaks down.....

 

Thanks.