carbon in intake

[punkytoole]

i was at the junkyard getting yet another power steering pump, and i was taking it off of a regal (with the 3.1) with the upper plenum removed. while i was working on taking the pump off, i couldnt help but notice the massive carbon buildup on the lower plenum. i scratched some off with my finger and it seemed to be at least 1/16" thick. this prompted me to imagine the carbon buildup that must be on my intake (and also reminded me why i hate EGR's). So i question as to wether its worth it to take apart my intake to see whats going on and try to clean any buildup and if i would need to replace gaskets and whatnot.

by the way, i have a 91 with the 3.1 with about 63000 miles.

[Manny_boy]

Whether its worth it or not depends on what you want to do your intake. If you just want to clean the carbon buildup you can get a can of GM Top Engine Cleaner from your Chevy Dealer (Part no. 1050002) (about $3 - $4 a can) get the liquid not the spray; That will take care of your carbon buildup issues.

If you do remove your intake, yes replace your gaskets, the intake gaskets for our cars a prone to failure.

Also, while your intake is off you can do a mild port & polish job on the throttle & the intake - smoother, increased airflow.

[jeffcoslacker]

Carbon in the intake won't really hurt much, but if it is loosened up and ends up stuck to a valve seat or piston head, you've got trouble. (causes detonation and/or valve burning)

The intake shouldn't really have that much buildup unless the engine it came from wasn't metering fuel correctly, and the EGR charge was real sooty.