Intake gasket job

[19Yukon97]

I just want to add my two cents here... i bought my truck 2 years ago, and when i got it i immediately knew it needed the a new intake. I bought parts and everything. Took me 3 hours to do the whole thing. Might take some people alittle longer. I knew what to do though. I rebuild engines with my dad over the drag racing offseason so i know what to do pretty much. Not saying you guys dont. But here's what i did... All of the "wire spider web" was taken off. and pushed back to the back of the engine compartment. then the process of bolts coming out. If your careful you dont need to take the valve covers off. Everything will go back on just fine if your careful. everything was cleaned and put back in the same order. Ive done this fix twice as i didnt have the money to get the upgraded fuel system the first time. Its not hard at all. Just make sure your careful. might want to plug the intake runners with paper towels so not to drop bad gasket material down in them. Let us know how it goes. Truck should run much better after this fix. I was noticing the same symptoms as you are and now they are gone.
Good luck!
Nick

 

[retorq]

I'm in the process of doing mine on my '92 Sierra right now. I'd advise changing your oil, because if the gaskets are bad then most likely coolant is in your oil.

Also, make sure to put thread sealant on the intake manifold bolts before you put them back in! If not oil will seep up through the bolts.

Only the 4 inner bolts on Vortecs go into oil galleys ... either way oil shouldn't be seeping past the bolts if your PCV system/crankcase evac system is functioning properly.

 

[purple 'hoe]

To the OP.

If it's ideling at 1100RPMS, then I would not assume Intake Manifold Gasket. Check for a vacuum leak like stated before. Unless you have a loss of coolant, then I would not assume intake manifold gasket yet. Possible that could be bad too, but that will not cause your high idle.

 

[retorq]

If your intake gasket was leaking air from the crankcase or atmosphere into the intake runner that would cause some idle issues ...

 

[purple 'hoe]

If your intake gasket was leaking air from the crankcase or atmosphere into the intake runner that would cause some idle issues ...

True. But I would not suspect Intake Manifold first. Not to say it's not a possibility, but I'd look at other areas first in this case.

 

[96ProCompTahoe]

did mine this fall. pretty easy, had to take off the valve covers as there was no way the intake was coming off with them on there. upgraded the spider assembly (was not functioning correcting).

took the machine shop 2 days to get the lower manifold cleaned up. night and day difference when it came back. upper took a long while and some soaking to get cleaned up as well. 190,000miles worth of crud built up in there

just keep track of your bolts, nut, and brackets. if you pull off the PS/AC bracket you'll need a puller for the PS pump pulley.

 

[992dr]

I did mine as well, twice in 4 days, hah. Take your time and pay attention. I removed my valve covers to, I figured if I'm replacing my intake manifold upper/lower, might as well replace the valve cover gaskets to. A little preventative maintanence.
I just moved the a/c bracket out of the way, it moved enough to get the manifold out without having to remove it completely or remove anything else.

Good Luck

 

[zzptahoe]

I really appreciate the discussion guys. Looks like ill have to to this in my house garage with snow on the ground ..anyway, I did remove the TB, Replaced IAC valve, cleaned TB with cleaner, I noticed the butterfly valve was hard to close all the way sometimes, like i doesnt seat or fit right, also replaced the tb gasket, cleaned MAF. None of that helped. Im running a K&N cone filter. I really dont know how to find a vacuum leak. Im a fish out of water:|

---------- Post added at 10:39 AM ---------- Previous post was at 10:36 AM ----------

Id also like to add, When you put it in D the idle goes down to about 800, kinda rough at times but I rather have that then 1100RPM! After driving it for awhile, and the engine gets warm there is a LOUD screech. Checked all the pulleys/belt the squeak is coming from the rear of the engine, around the TB i believe.

---------- Post added at 10:41 AM ---------- Previous post was at 10:39 AM ----------

One more thing..lol...Does Leak coolant from the radiator hose or something of that sort? When you start the truck from inside the cabin you can hear the engine slupring up coolant. I put about 1qt of oil in it every two weeks.