Hey guys. Ok here's the story. I have an 88 IROC Z vert, LB9, auto, 104,xxx miles on it. Now here's the problem(s): I have a fairly large oil leak comin from the back of the engine seems like, it leaks enough oil that once parked for the night you can see a good spot on the driveway from the spilled oil from the previous night. So i've taken a look at it and my mechanic has taken a look at it and neither of us can see where the leak is coming from. He says he's checked out the rear main seal at the back of the intake and thats not it either. Ok so besides taht, everytime on start up i have the bluish tinted smoke come out from my exhaust which i assume to be valve seals. But the thing that makes me think its not valve seals is the fact that after turning the car on and letting it idle you can smell the oil from the exhaust, and after about a minute or so smoke starts coming out a little bit and gradually the amount of smoke coming out of the exhaust increases. And on top of this all at WOT you can smell the oil from the car, i don't see any smoke but you can DEF smell it in the air. So my best guess would be head gasket? i don't even know anymore. ANY help will be greatly appreciated, and if i can't figure it out the car is gone, parents have threatened me with it. Thanks in advance

 

The oil smell under WOT , or just after a while could be leaking valve cover gaskets.
If there leaking onto the exaust manifold, the oil is burning off and thats the smell.
You said the mechanic checked the rear main,
have you checked the oil pan gasket, or the intake manifold.
It's not a head gasket. If it was a head gasket you would be getting coolant into the oil inside the engine, and you would be blowing white smoke.
Do you park on an incline at all?
The oil could be runnning down from the front and dripping by the back of the motor.
Your best bet is to buy some engine degreaser, clean the engine really good, then look for the leak.
Good luck in your search.

ps. The blue smoke definitly sounds like valve seals.

 

I'll change the valve cover gaskets asap tomorrow to see if thats the cause of the problem. that makes sense for oil smell at WOT but after a while the smoke comes out of my pipes, not from under the hood where the leaking oil is burning off the exhaust manifold. And also i do park on a slight incline at night, but i have parked in a level area overnight to test that theory out but same problem just slightly less amounts of it. And one more thing, how hard is it to put in new valve cover gaskets and valve seals and could someone point out wher ei could buy them with a link or something. Thanks guys

 

The seal at the back of the intake (china wall) and the rear main seal are two different seals. The only way to check the rear main is to drop the tranny and pull the flexplate off. The mechanic probably only checked the china wall. I second racerx's suggestion to clean the motor and then look for the leak. Could be your oil pan too.

www.gmpartsdirect.com sells good valve seals, 8 positive locking for your intake stems and 8 umbrellas for your exhaust. $25+$10 shipping. You can get valve cover gaskets and probably the valve seals from a local parts store. Do a search for replacing your valve seals, there are a couple different way of doing it - you can either stuff nylon rope in your cylinders or connect an air compressor to your spark plug hole.

 

i'd check the valve cover gaskets and the oil sender