OK so yesterday I decided to start my intake gasket replacement. 1st I unhooked the neg bat cable.then I drained the coolant, then I removed the intake boot and airbox cover in one piece. be sure to remove the air temp sensor 1st lol. I than began removing all the sensor connectors and vacume lines. and also all the plastic clips that hold the wire harness close to the engine.....a small flat screwdriver comes in handy for this. the fuel injector plugs are a little trickey and kinda fragile so be careful there.. lift up on the blue piece and then poke in on that grey metal tab just beneath it ...you may have to fiddle with em a little . at this point I found no need to lable anything as all the connectors have diff plugs and are placed in the harness close to the where they need to go anyhoo. even the injector plugs are placed inline in the harness so its unlikely to get em mixed up. now at this point I took the liberty to use my air compressor and bloe all the crud away from the intake. after that I used my shop vac to remove any remaining debris. I found this much easier to do with the wire harness moved away . next I removed the fuel rail and hung it up out of the way with a bungee cord. rather than depressurize the fuel system. there are 4 10mm nuts that hold the fuel rail to the intake. I then decided to remove the alternator and the coolant overflow bottle and the tensioner assembly to make things easier, of course the plastic elbows crumbled to pieces.
I decided to leave the throttle body on the upper intake plenum and remove as a unit.i just unhooked the two throttle and cruise cables. my car has a bolt instaed of a stud on that pesky bracket that goes to the LIM .....so I didn't have to bend it out of the way. after I removed all the upper plenum bolts it was pretty easy to get it all out from the left side. you will need 10mm and 8mm sockets for this.
The LIM was very easy to remove at this point. I removed all the bolts and put them in my chem clean bucket to soak overnight. 10mm here also. a little antifreeze will puddle under the thermostat. be careful not to spill into the engine when removing....just a tip. now it was getting late so I decided to call it aday. today I will clean up everything for reassembly and post some pics ,


no need to reply folks I'm going to add more to this post as it progresses.

 

 

Took 5 cans of brake clean to clean that dirty ol LIM what a project in itself.....dang! but I got her all clean and the heads too and mounted her up. I used the fel pro metal gasket set. I sure hope I made the right choice in that respect got the throttle body all cleaned up and mated to the brand new upgraded version upper plenum, pretty easy task there, most of my time today was spent cleaning up the cyl head surfaces......that was a lot of time consuming tedious work. and I also managed to get the front valve cover gasket changed out. sorry no pics.......I ran outta steam I am an old man after all still have to change out the rear valve cover gasket and then mount the upper plenum and wire everything back up...ill do that Monday. tom is rest day.


wait till you see the old gaskets and the plenum....pretty bad shape,good thing I tore into this now . it was a disaster just waiting .


I'm gonna pull a spark plug tom and see how it looks I'm not really up to it but if it looks bad now is a good time to swap those too I reakon.


man I am beat. good night!!!

 

Do you have the Dorman reinforced manifold?
My engine is approaching 80k, and want to do this myself instead of paying 600 bucks again, I also want to do the rear valve cover gasket

 

I got the ATP Automotive Graywerks 106001 Engine Intake Manifold from amazon it was 75 bucks and came with all the gaskets you will need. don't get the felpro plenum set it deosnt fit right and will break when you torque it down. the rear valve cover is a snap with the upper plenum off and you may want to remove the alternator also. makes life easier on the whole project.


here are sum pics


the last one is where I'm at now...almost done!! I'm not crazy about how the dorman coolant elbows fit however...they seem kinda loose to me

 

You were definitely due for a change, how many miles on ya monte? I was gonna get the fel pro aluminum gaskets for the LIM and the Dorman for the upper, that's what I used before

 

105k miles on original gaskets. I used the felpro metal LIM gaskets

 

why GM used plastic coolant elbow on the intake I'll never understand

 

Per the Bonneville guys, I believe ATP is supposed to be the best replacement UIM on the market.

The Fel-Pro metal core LIM gaskets are definitely the way to go. I've used them when I installed my port matched LIM and so far those gaskets are working great.

Replacing the LIM gaskets is a fairly easy task on these cars, but as stated, cleaning the LIM and other parts can be a pain and a project in itself.

 

I finished it up today engine fired right up. no leaks! no milkshake!


kinda of a pain getting the air out of the cooling system tho....made me nervous watching the temp gauge climb cant help but be a lil paranoid after a job like that. I have a bad back so it was a pretty big project for me. but ita all back together and the engine fires up like a match. ill keep an eye out for leaks tom while I do a cple test drives. thanks to the forum for all tips car runs smooth as a sewing machine so I decided to do the spark plugs at a later date.