I checked my oil yesterday while getting fuel, and I noticed that the oil is nearly black - after 2200 miles. Anyone know what might cause this? I haven't had it to the track since the last oil change.

 

David Lively,

Seems that you are getting some blow by. Mine did that when it had less than 6K miles on it. It has gradually improved with more miles and at 22K miles, the oil still looks pretty good at 3k.

If you have low miles on her I would expect an improvement as the rings continue to seat.

Good luck.
Mark

 

OMG, could be a major issue!!! :smash: :smash:

Have you ever gotten the "low oil pressure" warning on start up?

Have you ever had any oil pressure issues?

I had my engine rebuilt because GM ignored my concerns about a bad oil pump...mainly a sticking open oil pressure relief valve.

They dicked around replacing lifters, and then pulling the oil pans and found coked oil (burnt) in the pan and oil pick up tube. Each time they said cool let's replace the lifters (not addressing the problem) and then they cleaned up the burnt oil and replaced the oil pick up tube.

They thought this was how to deal with this. OMG, they didn't have a clue as addressing the problem, just trying to get the car back on the road again.

O.K. i'm taking some deap breaths now, because I just want to :smash: :smash: :smash: :smash: :smash: :smash: somebody's head @ GM each time I think about this...

Anyway, they finaly took the engine apart and found a stuck open oil pressure relif valve (stuck open with freakin loctite). I demanded to have the main bearings inspected because I told them the oil was getting "coked" from a freakin red hot bearing. they found the furthest from the oil pump "scratched"

GM rebuilt the engine and bored the block to put in hand fitted pistons because I mentioned that the engine was using oil.

Damn these are the best sports cars on the planet, but they do have some weakness's.

It burns me up to here the press call the C5 "the best bang for the buck". Yeah you put up $20g's less but (when you put it to the test) you pay the price. I've put up $10'g in mods to be equal (actually better) thean the Z06, and still have major issues with GM's Chevy (excuse for service) service network. :smash: :smash:

Where's that brown paper bag...i'm starting to hyperventilate.

 

You probably drive a lot of short distance trips so the oil never gets really up to operating temperatures.

Roger

 

Thanks for the suggestions. Car has 33k miles (getting close to that warranty expiration), had rings replaced about 6k miles ago under warranty because of blow-by. I check the oil frequently and I've never noticed it that color before.

20+miles from home to work, usually take the truck for short hops to the store and back.

Now this has me concerned, especially since the engine was just recently reassembled. I do notice that the oil pressure at idle will fluctuate between 30 psi and 25psi, sometimes dipping as low as 20psi. Pointed this out to the dealer, they say it's normal for it to fluctuate. Takes three to four minutes for it to move from 30 to 20 and back, and it doesn't always happen. Any way to diagnose this without ripping the engine apart?

I've also noticed a bit of oil puffing out of the exhaust when following a friend of mine (who was driving my car) when up-shifting. Hmmm... I'm guessing that lifting off of the throttle at high RPM increases the cylinder pressure momentarily, forcing oil past the rings. Hmmm..

Any more suggestions? Should I take it in and start raising holy terror?

 

David,

I would definitely get it documented before the warranty expires. That way it can still be subject to a warranty repair should that become necessary. It doesn't sound to me that it should be using that much oil after a re-ring job to correct blow by and oil consumption.

Good luck.
Mark