Hey guys. Im having problems with my oil pressure.

What happens:
I start the car, runs a bit rough, oil pressure at 3/4 on the gauge. Then once it warms up runs at 1/4 on the gauge while driving. When I come to a stand still like a street light or shifting to reverse (auto) the car immediately drops into the red and says check engine! I have to put it into neutral and give it gas so the rpm's will bring the oil pressure back up just over red line. I think it may have made a knock sound once but caught me off guard so Im not sure what the sound was. Also car tends to overheat a bit, 3/4 on gauge so I have to run the defrost to lower temp.

Also the oil pressure goes up and down with the rpms when running warm. Runs warm around 1/8 to 1/4 over red line when driving

What the mechanics have mentioned:

One mechanic said that it was my oil pump... going. He told me to replace with a high volume pump. Another said it could be your cam bearings, common as well in camaro's.

How do I fix this before I blow my engine? Is there any advice on what the problem may be? How can I trouble shoot myself? I have the OBD1 &2 scan tool but pulls no codes.

1996 LT1 Z28 5.7


Sorry guys I didn't find a post that could be closely related to my problems (and was a lt1)

Any help MUCH appreciated!!

 

I'll bet it says "check gauges" not "check engine".

It could be a faulty oil pressure sensor. You could put a mechanical gauge on it to verify the actual pressure.

Cam bearings are not a common problem on LT1s and you DO NOT want to run an HV pump with a stock pan. Bad advice, there.

Oil pressure, in itself, will cause no trouble codes.

As for your overheating, make sure your coolant level is ok and fans are working.

 

are you using synthetic? with alot of miles and thin oil, maybe you just need to run a 20-50. cheap fix,if it works.....good luck.

 

It sounds like the oil pick up fell off the pump.It is common.

 

How many miles are on the car?

 

My engine builder was going to be putting in a Melling HV pump in my car... what's the problem with those?

 

Nothing wrong with the pump, but it can suck a stock pan dry. It also puts extra stress on the oil pump drive and they like to strip. Either can cause loss of oil pressure and ruin your engine. An HV pump is not needed unless your have specific oil clearance needs for it. There are plenty of threads on this forum about HV pumps and problems.

 

OK, thanks for the heads up

 

just had one last week that drove for a while and the rocker arm was off to the side and pushing on the valve retainer. oil pressure was low,made noise, had slight miss at idle. ran a little hot. just had a head gasket replacement.. you siad you heard a noise. i doubt it is the same but my 2cents

 

Hey guys sorry computer was down.

I forgot to mention that I did take the camaro in a little while ago. They tested the oil pressure and said it idled at 12psi but I don't think it was hitting the red on them. They said the oil sending wire was faulty so they replaced the wire I don't think the sending unit. $200 dollars later and the problem is still there.

The rockers are making noise and there is a slight hesitation at idle. I have 160, 000 km on the engine. The engine and rockers are all original stock. I was running regular 5/30 oil but now I am running 15/30 to try to build oil pressure.

I just ran the car tonight and I didn't realize while it was running at the drive through that it was in the red. No knocking which is really good but red line is not good!

I topped up the coolent and bled the lines as to shoeboxes recommendations, only seems to get hot when its 20 degrees Celsius or more outside. (what ever that is in fahrenheit lol)

I also have read that you need a bigger oil pan for more pressure.
Shoebox, you don't think its a worn out pump? Could it be as easy as a oil pickup that might have fallen off? Or maybe something to do with my rockers? I put my scanner on it and like you say there is no codes and yes it was check gauges. Im totally stressed and don't have lots of money to go nuts on this. Thanks for all your input so far, really appreciated!!

 

One more question, is the oil pump located in the oil pan? I read the Haynes manual and it mentioned lifting the engine up 3 inches to get to the oil pan and the oil pump I think.

 

How was the 12 psi determined? Did they put a mechanical gauge on it? They replaced the wire, but not the sensor? 12 is low, but enough to keep you out of trouble at idle.

Yes, the pump is in the oil pan. Even if the pickup was off, sitting level at idle, the pump inlet should not be uncovered with the proper oil level. Under hard braking or acceleration is usually when people notice low pressure and that their pickup might be off. You could drain the oil and bang on the bottom of the pan. If the pickup was laying there, it would bounce and rattle around.

A pump might help, but with 160k miles, you have to consider that it might just be bearing wear taking your oil pressure down.

 

Is it at all possible there is a buildup of debris in the stock oil cooler causing the problems? I just pulled mine off my '94 and while it was mostly clean, there were a few chunks of crud stuck in it.

 

I believe they put a gauge on the engine somewhere to test the oil pressure. But ya, like I said it wasn't in the red when they were testing at all so Im not too sure if there test got all the results.
Im not sure what to do about this problem and how to diagnose it with out ripping the engine apart. The oil seemed fine, there may have been a bit of a gritty feeling to the oil but it seemed clean and fine. When I take off and slow down, I don't think the oil pressure gauge moves, and if it does its not much. The pressure seems to chase the rmp's of the engine. When I throttle up, oil pressure goes up to 1/4 mark. When I slow down, oil drops and then stop, it hits red. (when running warm) When it first starts cold its at 3/4 on the pressure gauge.

I was looking at your tear down for removing the cam shaft to get to the cam bearings and I think that might be a little over my head. What would be the best things to do to diagnose this. Seems like the electrical aspect of the engine is not helpful so I might have to start with the oil pan/pump and head towards the cam.

As side note... its 160km not miles, not sure if that makes a difference.


There is a oil cooler on my car? Never heard of that.

 

No, your car has no stock oil cooler. If they checked the pressure with a mechanical gauge and it was 12 psi, but your gauge still reads low and they did not replace the sensor, then I would say you need to try a new sensor.