Thread: 1999 GT Coupe

Originally Posted by VGPGT

Bill - Thanks I was wondering about that.

I did replace both the upper and lower intake gaskets. I'll remove the spark plugs and do it again plus I'll clean up the plugs. Maybe I can do this Friday evening for I'm busy with working 2 jobs today and tomorrow.

This is the longest slowest repair ever... I just hope this car runs after all this.

no no. i think you misunderstood. i think Bill is referring to the UIM, the whole big black plastic piece on top of the LIM. you need a new one of those. they are VERY common about leaking because the EGR causes it to melt.

OK - Now I REALLY Understand !!!

So....next question is can I use silcone or something to temporarily fix this? I only ask because I'm sticking more $$$ into a engine on a car that I know else nothing about... I think I know my own answer but its partially killing me to go buy another part...

I have found out this Grand Prix has new brakes relatively new brakes.

What actually happens is the many heat cycles crack it.. not melt it. But...yeah..whatev

Easiest fix to keeping the UIM from cracking is to pull it off, clean and rough up the coolant tubes, then fill them with JB Weld. Another way is to drill/tap the LIM (yes you can do it on the car, not recommened if there's a choice..but you just did the gaskets) and use 1/4" npt pipe plugs. that'll stop the coolant ...without coolant in those tubes going past the EGR stovepipe hole..there's no risk of filling the motor again.

I've put a piece of vacuum tube on a blow gun and blown out the cylinders before. But really..dry a couple more plugs..get three to fire and keep your foot on it.. it'll clear.

yes, so long as your're not leaking anymore, just get enough of the plugs cleaned up and all the coolant you can out and do everything in your power to get it going. starter fluid if you need. once it's running it's gonna burn/blow all that sh1t out.

also, when i had this problem (before the engine blew haha), it took many many many tries to get it to crank up because the PCM apparently had to re-configure as the burning coolant had knocked it out of whack i suppose. the reason i say this is because once it started running, it ran like crap and sounded like it kept choking out but it eventually sped up and smoothed out, gave one BIG rev and then purred like a kitten. so don't freak out if at first she doesn't crank or cranks and runs like crap. give it time to get it's numbers straight.

It runs!

Saturday morning I finally got a chance to work on this again. I installed a new UIM, 6 new Iridium plugs(after buying Bosch Platnum 2s and returning them), all new injector o-rings. I turned the key and it started! I let it run for about minute then turned it off, changed oil, filled it with coolant, then took it for a drive !!! I have driven it a whole 10 miles... Tomorrow I might take it for long drive - 33 miles round trip to work and back home.

I was SO happy when I turned the key and it started !!!

One mistake I made was failing to correctly follow the plug wires to the back 3 cylinders, the harness had several of the wire separator snap things on it and the last one in the back had 2 wires switched...oops Next time I'll follow these better! I also had an o-ring leak on cylinder #6, the car was running a good 5 minutes before I noticed, hmm gas spilling down right by the exhaust. I took the injectors off again and found this one to be ripped a bit, i put on a new one pressure tested it and re-installed the injectors.

It drives like a car with 200k miles in it. I should know I now have 3 with over 200K and my wife's Limited Edition has 183K. My '97 coupe has the most miles - 220 something and I think it rides the best. Time to update my sig line.

Again I bought this car just for the tires and for approx $200 and some time learning things I have another GT !!!

Thank you guys for all your help !!!!!

lol im glad to hear that. yeah, always replace injector o-rings when removing the fuel rail. just saves you time in the future.

Brandon, I did replace all the o-rings, one just got ripped during install I guess... seemed odd but all's well now!

Drove the car to work today, heater blower fan likes to squeal rather loudly at times. I'd adjust the speed and it would go away then come back randomly. Guess I need to look at that soon.

And the front suspension on the passenger side make noise when I hit a bump in the road.

It drives straight, brakes work great, trans fluid looks to be old, the car has excellent power, get up and go is as good or better than my others.

well that's good to hear.

as far as the motor, try spraying wd-40 in the hole on the center of the blower motor. rather easy to get to from what i understand.

the noise in the suspension is probably strut mounts just guessing..not sure how many miles u have.