I bought my son a 2000 Camaro with a V6. Other than some odds and ends. It runs really good. The oil pressure has been a little wacky though. I think it's a bad oil pump. At cold start, it has 60 psi. After warm up, and cruising at 55 mph, it shows 30 psi. When stopping at a light or stop sign, it goes to almost 0. Check guages light comes on. Lots of lifter/rocker clatter. Take off and pressure is back up to 60 psi and so on. We just changed the oil also. Put in full synthetic. Still does the same thing.

 

It could be a oil pump or it could be too much clearance in the bearings. I have not heard of the oil pumps failing like this on a SII 3800. At least it is not a common problem. Depending on how the car was cared for you could have sludge in the pickup tube. It sucks because pulling the oil pump and the oil pan is a pain in the car and if it turns out to be a bearing issue all that was wasted work.

Normally I tell people to confirm oil pressure with a hand held gage but if you are getting noisy lifters that quiet with oil pressure then in this case the gage is reading right.

On the plus side low miles 3800's should be cheap and plentiful.

 

The oil was very black and thicker than I've ever let oil get. The pressure was still doing the same before the oil change, just not as quickly as it does now. Probably has something to do with a new thermostat being installed. Now the engine gets up normal operating temps. Either way, sounds like the oil pan needs to be dropped, and if I go that far, then I'll probably put in a new oil pump anyways.

I've watched some videos of an engine swap. I definitely don't have the tools to do that, mainly a way to lift the car off the uni-body.

Thanks for replying.

Roland

 

How many miles on it? sounds like the main bearings are toast to me. If it's getting 60 psi cold and 30 going down the road it's pumping oil.

 

153,xxx miles.

 

I'm not sure if it's lifter clatter. I easier to hear the knocking while you're in the car, and not with the hood up. Sounds deeper in the engine. Also, the knock is definitely consistent with RPMs.

 

I'd still put my money on main bearings being about gone.

 

post a recording. pull your oil filter or if you have the old one cut it open. open up the pleats on the filter and see if they have metal particles in them.

 

might be time to look for a series 3 3.8 with low miles. i found a good one with 60k miles with good compression for 400 bucks. had the heads checked so replaced the head gaskets up. probly 150 bucks in gaskets and the new stretch bolts. https://camaroforums.com/forum/93-02...nt-info-57568/

 

FYI the oil pump is not in the oil pan on the 3800. Its in the timing chain cover.

As a general rule, if it's bearing knock without a load (at idle) its a rod bearing if the knock gets worse under load then it is a main bearing.

If you open the hood and switch your head positions from under the car and under the hood. Low noises are almost always bearings. Noises louder on top are normally valve train. The gray area is wrist pin and piston slap. They can go either way. An experienced mechanic can probably tell with 95% accuracy by sound just by sound.

The first symptom of low oil pressure should be valve noise on a motor in "normal" condition. Oil pressure drops the farther it gets from the pump and the lifters are last in line. An older engine can have 10-15 PSI of oil at the crank and have near zero at the lifters.

If lifter/valve noise is not the symptom then I would recommend a manual check of the oil pressure. Factory gages are crap, next to useless for diagnosis. If you are seeing 10 PSI at the top of the engine at idle it should not be making noise. A high volume oil pump may make the sound go away but there are other oiling issues and the oil pump replacement is more a temp Band-Aid then an actual repair.