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L98 Oil Leak


Sep 3, 2020
1990 Charcoal Z51 Coupe
Hello, I've been chasing down an oil leak on my 1990. I thought it was coming from the valley seal, but I've done the intake manifold three times now to no avail. There is no oil coming from the distributor shaft seal, and no oil on the pressure sender. You can see a trail of oil coming down on the driver side at the rear from right where the head, block, and intake manifold meet. I would swear it was the intake manifold if I hadn't already done it three times. It's coating the bottom of the car in oil, so I'd really like to get it fixed. Is my next step doing the head gaskets?

Thanks in advance,
I have not, but it looks totally dry on the head, I only see oil on the block.

I would say somewhere in that mess of connections if thats the area.
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View attachment 46101
I would say somewhere in that mess of connections if thats the area.
I know the sensors aren't leaking, but I don't have that pipe underneath them. Is that an oil pipe between the heads? An LT1 thing? Would the plumbing for it be on my heads, too? I wonder if that could be it.
There's another view with the manifold removed looking towards the firewall on that link,just page down on it.
Thats for the l98,the lt1 has the opti spark dissy in the front of the motor.that pipe on the heads is for the steam pocket crossover.
BTW,if you remove that molding on the firewall that holds the hood seal on you can see that area better, its only held on by those torque screws,remove the screws & it comes right off.
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