Introduction, I own a 2 door n/a 99 gt. 205k miles, still sharp as ever other than a few minor details. The drivetrain is where my concern lies. I have had TWO less than 80k replacement motors.. The original just started running very poor and something just gave... The second one, almost the same occurance. I was driving down the highway, less than two months after the dealer had replaced the previous engine and it just got a horrible top end knock.. Before I could get it off of the highway, something broke, smoke and oil was everywhere. No clue what went wrong.. Was just too pissed to care and wanted another engine. Now onto this one, every so often, on warm starts, it has a rough idle to it. Enough to feel. If I put it in drive, it will smooth out and run just fine. The previous two motors did this before blowing so it has me concerned. I know I am being vague but don't really know how to describe it more so. Any tips? Suggestions? Experiences?
New here! few questions :)
- Thread starter wilk84
- Start date
Hippo Machine
Because Wet Leaves
These engines are prone to LIM gaskets failing, causing coolant to get into the oil, leading to rod knock, which sounds like what was your problem the last 2 times. TO prevent this, you have to replace the gasket with an aluminum one. Not sure about the running rough, maybe elaborate on it or get a video. Last oil change? Keep an eye on coolant level.
On a scale of 1-10, how difficult is the gasket change? I'm will to take any precationary route to keep this engine 
I changed the oil roughly two months ago.. Not many miles since then. Oil looked fine, just stretched the last oil change to about 7,000 miles due to it being a "new" motor... Wanted to see if there were any surprises with it.
I changed the oil roughly two months ago.. Not many miles since then. Oil looked fine, just stretched the last oil change to about 7,000 miles due to it being a "new" motor... Wanted to see if there were any surprises with it.
BlackGT97
New member
with someone who is good with tools and has a fair amount of mechanics, probably like a 4. if you have no idea what you are doing probably like a 7 or 8. but there is a write up on how to do it, and plenty of us will give you help if needed. And hippo, you are forgetting that the glassed filled nylon intakes we got warp when they get hot. and the EGR tube likes to "melt" away the intake which will also cause coolant to be burned, therefor the upper intake should be replaced with a new intake manifold.
Hippo Machine
Because Wet Leaves
I haven't done it but would say a 5-6 there is a how to video somewhere on here but here is a thread: http://www.grandprixforums.net/lim-gasket-replacement-2-46950.html
Fill up the coolant and make sure it isn't goin anywhere and post up a vid if possible.
Fill up the coolant and make sure it isn't goin anywhere and post up a vid if possible.
BlackGT97
New member
to get the best prices order online and enter promo VISA when you check out. (at advancedautoparts.com )
If you going to do it, you'll need the LIM gaskets-around 75 bucks for the aluminum ones
and UIM gaskets-around 40 bucks. should get it all for about 80 bucks with the promotional code.
If you going to do it, you'll need the LIM gaskets-around 75 bucks for the aluminum ones
and UIM gaskets-around 40 bucks. should get it all for about 80 bucks with the promotional code.
SlowNA06
New member
This is not likely to be a LIM gasket failure. I wouldn't be worried about it in your position.
To clarify, what we have is a rough idle in PARK, but no symptoms in DRIVE.
BlackGT97
New member
True: the LIM gaskets is not the cause of this problem....but every 3800 owner should be worried about it if they don't know what conditon their LIM gaskets are in.
That's correct. No codes, engine light has never come on. Once the car has warmed up, say if I shut it off and run into a store for example.. Upon starting it, it has a very lopey idle but once I put it in drive and accelerate, it smooths outs and has zero issues. I bought bosch platinum +4 plugs yesterday but took them back for AC DELCO iridium plugs today. I got the front three in but wasn't able to get the rear three. Couldn't get the wires off (cold and rainy, was tired of trying). I also bought a new fuel filter which I plan on changing tomorrow as well as running some Lucas through it... Just has me puzzled...