I just purchased some Fel-pro Intake Manifold Gaskets MS93317for my 92 Chevy Camaro. I was wondering if I should have cut out the rear coolant passages on the gaskets. I wasn't sure, so I installed them without taking them out. Now it is running awful, it cannot hold an idle and a hissing noise is heard from it. Also, I only get heat out of the defrost vents. What happened? Is it out of time; Are there more gaskets I should have replaced? Also the vacuum tee running to the fuel pump may be not hooked correctly..... Any advice would be appreciated....... Does any know Anyone in my Area that can fix this problem? Money isn't too much of a problem..

 

If your manifold has a water passage back there, you need to open up the gaskets.

IIRC, only the stock Corvette TPI maifold has a water passage at the rear of the manifold.

Sounds like you have a big vacuum leak someplace.

 

You definitely have a bad vacuum leak, and only getting heat through the defrost vents is a certain indication of that. Your selector door in the heater box is controlled by vacuum, and the line for it is supposed to be connected to the vacuum tee on the intake manifold in front of the distributor. Check all the vacuum lines that go to that tee and make sure they're all hooked up properly. All your problems with it running horrible are more than likely from the vacuum leak. You'll also want to hook up a timing light and make sure you've got the timing set right while you're at it. Since you had to remove the distributor to change the gaskets, you definitely need to check and set the timing again. Make sure you disconnect the single tan/black stripe wire that comes out of the main engine harness over by the A/C doghouse before you adjust the timing and hook it back up once you have the timing set where it needs to be. I've seen intake manifold gaskets installed with or without the rear ports blocked, and it doesn't usually make much difference either way, so unless you get overheating problems, I wouldn't worry about it.

 

do you know where i can find a diagram for that vacuum tee?