Thread: LIM Gasket's

I am in the middle of my tear down and I have just removed the UIM.

The inside is very black and has lots of residue. The LIM has not been removed yet. There are pools of oil on the top cavities of the LIM.

Why is there oil here?

Is there something more to replace than the UIM, LIM, and throttle body gaskets?

Any help would be appreciated.

Its normal....this is what mine looked like at 123K

About three rolls of paper towel and 3 cans of cleaner worked.

Originally Posted by FordMan77

Totally normal. Just soak up all the oil so you can find the 2 hiddem LIM bolts. Should be one in the back pass. side and one in the front drivers side. People miss those all the time and wonder why a 6 foot pry bar doesn't take the LIM off, lol... BTW, do not use a pry bar

I won't lie, I did that... also put the LIM back on without the gaskets....

Thanks for the info. Is the oil there because of the bad gasket?

How well do I need to clean the inside of the plenum? mine is black with a nice layer on it.

make it shine if you can, brake clean the piss out of it.

Originally Posted by Pepino

I won't lie, I did that... also put the LIM back on without the gaskets....

you phail. royally.

bought more brake clean, will the plastic removable piece inside the plenum hold up to the cleaner? or what should i use on it?

thanks.

the cleaner shouldn't hurt plastic or anything like that. when i had the GT i never cleaned the UIM, but it couldn't hurt. more specifically, use the brake clean to clean up the lower intake, the heads, the valve covers, that kinda thing. anywhere gaskets are going you want them oil free. i would always rub brake clean over the gasket surface of the UIM, but i'm sure it wouldn't hurt to get up in there and get any dirt out.

Well everything worked out well this weekend.

Flushed the coolant, changed out the gaskets, LIM, UIM or plenum, throttle body gasket, new valve cover gaskets, new temp sensor, new coolant elbows, cleaned the hell out of the lower intake, plenum and throttle body.

Improvements: GP runs really smooth and starts up with a slight turn. no more start and stall.

Now lets hope the coolant level stays where its suppose too.

Thank you all for your help.

Ok a little problem here.

It has been about 3500 miles since the new AC Delco LIM gasket and UIM gasket. I did every detail, ultra permatex copper in the 4 corners, clean the up everything, and torqued to spec in order.

Now I have white smoke out my tail pipe again and the coolant is disappearing inside the engine. Little less than 1/2 a qt a week.

Could it be coming in another place than the LIM? like the egr tube?

Does anyone have some insight on what I should do? Was thinking about taking it to a mechanic, how would they diagnose the issue? Anyone know of a recommended place in Orlando, Fl?

Being an 05, you have a metal upper intake plenum, right? The only places I can think of would be at the TB to upper intake, or the LIM to upper intake. Those gaskets can leak into the intake. I've yet to ever see an aluminum intake gasket leak.

i mean if you don't have a way to swap the plastic for the aluminum gaskets it's not the end of the world. they could last you 150k miles who knows

if it has some miles, get a new uim gasket as well. tb gasket...meh, dont take the tb off if you dont wanna. but it is a good idea to clean it. you should replace injector o-rings. those are important. wouldn't wanna risk engine fire.

and the word you're looking for is facepalm. or

You can use the plastic ones. It's not like they don't work. Plan on replacing them again in 70-100K miles. GT1 in your year is an NA motor correct? Yes you can resuse that UIM gasket. You should have a metal upper intake, that's good. I'd replace the TB gasket and clean the TB well.

LIM bolts= 11 lb ft
UIM bolts= 89 lb in
VC bolts= 89 lb in

honestly, just snug em all by hand is what i normally do, if you're comfortable with that.

Haha. Not a problem. In fact if you have any other detailed questions, gpona.com (once you are a registered member) has access to the GM Service Manual. I find it quite helpful for the little things.

Good luck!