+1 on z28pete's post.

If the oil pressure is normal except when the engine overheats, then the overheating is probably causing the oil pressure problem.

However, if you have low oil pressure all of the time, I would definitely check that first as it will potentially kill your engine.

bcbarbie - What is the oil pressure when you first start the car in the morning?

 

i agree as well that over heating will drop oil pressure but it shouldn't drop it to the point you have no pressure.

i had this problem where low oil psi on my lt1 for a whole summer. when the car got a little over 210-220 the oil pressure would go from 35 to 8-6 psi which doesnt read on the gauge at idle. we tried changing the weights of the oi itand that had no affect on it. people tried to tell me this was normal and it met the service limit but i was never comfortable with it. after talking to mechanics and machine shops they all said if its at the service limit that means it need to be fixed not that its okay.

We never really figured out the cause but the machine shop said it could have been a worn pump or the bearings in the block. In the end i rebuilt the engine and my oil psi never drops below 40 at idle now.

 

well the oil pressure is fine when started, its after the car starts to warm up and driven or idle that it all goes for ****s.

 

That means that the overheating is causing the low oil pressure.
Fix the overheating and the oil pressure should fix itself.


x01660

 

I would not bet the whole farm on this, but I would bet a lot of it on this quote.

 

barbie, you never stated what actual temperature the engine was getting to, only that it was "overheating". These cars generally do run hot, and everybody has a different idea of what too hot means. What is the gauge telling you?

 

mine exhibited the same symptoms she described with out over heating. I also dont feel that this is really a true statement. oil is pretty thick bellow 100 degrees soon as it get to 180-190 it thins out pretty good. if you have an issue with bearings or your oil pump it might not become apparent till it thins out a little. Like what happened to me. Im not saying it is her problem but it is a possibility. i have had a lot of vehicles with over heating issues seen them lose a few psi but have never seen them drop off to almost no oil pressure as well.

like i said i had the same symptoms and have pictures of the guages and temps.

another thing barbie dont go off the cars gauge cluster mine is about 10-20 psi off of what it actually is. you need to hook up a manual gauge and check.

 

ok everybody, just had the rad flushed, and seems to be not overheating anymore, but now there is a new problem that has come about. Car had sat for a few years, ran only for couple months in summer then stored, ran real good for awhile after taken out of storage, then ****ty now, been using lower octane fuel, and i may have had a bad tank of gas too. Car runs rough,bogs down when you accelerate, stalling out, little backfiring, exaust stinks, and a faint noise under acceleration (paint can shaking sound) until RPM goes up . Put all new fuel in, and octane boost, new oil filter, oil, new fuel filter, new spark plugs, new battery, what could be causing this she's gutless when you stomp on it until the rpm's go up. very frustrating!

 

you guys helped with the first problem so lets see if you can figure this one out for me? mechanic that worked on it originally said the motor was done, it only has 34,000kms on it, and i just broke it in, what do you guys think?

 

check fuel pressure and catalytic converter.