jlaw

I pulled my tranny out yesterday (had it rebuilt, 3rd gear was howling, builder is fixing it) and when I got the car in the air, I noticed oil all over the passenger side of my ORY, all over the p/s of the pan, tranny, starter, etc. It wasn't pouring over everything, but it was stained and fresh.

Pulled the tranny, and there was oil inside the bellhousing as well. First thought was rear main seal... pulled the bellhousing, clutch, and flywheel off, but the seal was dry. Looking at the motor from the back, the top back of the intake area seems to be soaked. I didn't see anything coming directly from a valve cover, but there was oil in that vicinity as well.

Any ideas on a possible source? Lifter valley cover?

Chris@AP-Engineering

iTrader: (-2)

Most likely it's your valve cover gasket. Take off your valve cover and inspect the gasket, you might have a tear or it could have moved out of it's groove. The valley cover gasket does not see that much oil up there to leak that bad.

Let us know what you find.

Oscar Will

Look around the oil switch area at the top/rear of the block, since you had the trans out the engine may have rocked back as the trans came out and tweaked the oil switch.

jlaw

Bump... still there, lost approximately 1qt in ~1500 miles of mostly highway driving. I just haven't had time to deal with it.

I checked the valve covers, they're fine.

What are all possible sources of a leak from the top of the motor/back of the intake? Oil pressure sensor, cam sensor, knock sensor/valley cover, what else? The sensors are too pricy to play guessing games with, I need some way of narrowing it down.

ss rally red

iTrader: (8)

Just an idea,clean the motor with degreaser(Simple Green, Castrol Super clean,etc) and if you have access to a lift/ramps etc, after cleaning it let it run for 20 minutes or so and the leak should be obvious. Hope this helps,we have used this method for years.

cyphur

iTrader: (10)

That they are. Its easy to narrow down your OPS(oil pressure sender), the tall one that everyone breaks when swapping intakes. Generally when you break that one, your oil pressure guage spikes to hell or is non-op. Mine spiked to hell, but only after a few thousand miles....and a few hundred after that oil was ALL over the back of my motor, flooded my bellhousing, sank my clutch, etc. Good excuse to upgrade to a Spec 3, but really shitty reason for all that work. Check it out, it caused the exact same problems for me that you're describing. Hope this helps.

Purdone

Just took my 2004 GTO in for an oil leak. Dealer told me it most like the cam sensor and are replacing it. Based on this thread, that sounds like it is a possible culprit of oil leaks. Car had 230 miles on it, and was 2 days old. I was a little miffed, to say the least. Where is the cam sensor on this motor?

CharlieLed

iTrader: (1)

Sensor is on the top behind the intake. The sensor is a good place to look for a leak but it is not necessary to replace the whole sensor just to fix a leak. The sensor has an o-ring seal that can be replaced...o-rings are easily pinched when installed and can cause the kind of leak you are seeing. If GM doesn't sell the seal seperately then it can be gotten from many other sources...