Intake Mainfold Questions
 

I have been having issues with the v6 for a while now. I have had it into Chevy a few times with no solutions. The car will backfire into the intake, and pops and generally runs poor. The last dealer thought it might be a leak in the intake manifold, and in reading through the forum, it seems likely.

Replacing the o-rings looks fairly simple, but I am not able to find much information about the process. Are there any pointers to look out for while removing/replacing the manifold?

Also, is the dealer the only place to get the o-rings? Is there anything else I should replace while Im there?

Thank you,

Cj

The manifold gasket is GM part#12590958 available on Ebay for $19.94 shipped-
Disconnect the air intake in front, unplug the electrical connection to the throttle body, remove the 8 bolts holding the intake manifold in place (5 on top, 3 in the back), and disconnect the brake vacuum line on the drivers side. On the passenger side, remove the 10mm bolt holding the crankcase vacuum line and remove from the top/front of the manifold.

Lift off the intake and swap out the gaskets. Don't mix up the bolts- some are slightly different lengths. Re-assemble and torque bolts to 18lb/ft.
Have fun!
http://i.ebayimg.com/00/s/MzU4WDUwMA...U~hI~/$_12.JPG

Thank you very much. Incredibly helpful!

Cj

You are welcome.

A couple of tips- the bolts holding the manifold are all 13mm I believe (don't worry about the small ones holding the "lid" on the plenum cover, they can stay put), but the two horizontal 13mm in the back are the "knuckle busters" unless you've got a racheting box wrench. Then they're easy.

Also when you disconnect the throttle body, if you don't also disconnect the battery first, when you first restart the car you'll get a check engine light. It will reset after a few starts if you don't want to take the time. :nod:

Replaced the gasket last weekend. Thank you very much, the instructions were awesome to avoid a lot of headaches. I wouldn't have found those 3 bolts in the back easily.

Been driving for a week now, and haven't had the engine light come back on, and the car is running notably better Fingers crossed that this solves that issue. 1 thing I will be doing is adding the oil catch can, seems like a good idea after reading about them.

Thank you again,

Cj

Did you clean out the manifold? I clean mine out every time I change the oil. I'm having slight hesitation, I'm thinking it's the fuel injectors, need flushing.

You're welcome Cj, just let us know if you have any other problems and I hope everything continues to run smoothly from here out. :nod: