THIS IS EXTREAMLY LONG BUT REALLY DESPRITE FOR SOMEONE WHO IS VERY SERIOUS ABOUT GRAND PRIX PERFORMANCE TO HELP ME exaust has a gagling/rattle noise and getting worse, on take off, and when i accelerate it almost seems like it doesent downshift and it bogg's down and gargle is loud sounds like from exaust i have already bought a dhp pcm second hand but updated, but have not installed it yet, i had mentioned before i bough some parts from PFYC, a 3.4 pully and a 3.2 pully just to have maybe change in the future, im going with the 3.4 for now, gator back v-belt's, speedbuilt fenderwell intake, which is already installed, and a 180 degree thermostate. and im about to purchase the straight pipe to replace the u-bend, and some coolant, give er a nice coolant flush, i have already replaced fuel filter, and pump, ignition coil, two plug wires, and air intake. BUT!, i heard that if you add an air intake, new pcm, thermostate, and what ever else, that it could make my problem even worst, but then again what is the problem, could be 100 different things, i stayed up till 3am this morning doing research trying to figure out what it could be, with the symptoms i have, this is a list of all the possibilities, here they are,

TOURQE CONVERTER
SPARK PLUGS (ive already changed)
FUEL INJECTION SYSTEM ADJUSTMENT
FUEL FILTER (ive already changed)
FAULTY SPARK PLUG WIRES
INTAKE MANIFOLD AIR LEAK
VACUMM LEAK
DEFECTIVE/NOT FUNCTIONING RIGHT ECM
FAULTY COILS (could be did change one when i first bought it last fall, coil tower was rusted)
BRAKES BINDING (everytime i start the car and put it in gear and start moving there is always a quick rubbing sound in the front like when anti-locks activated the sound it makes it the same is this normal?)
TRANNY FLUID LEVEL INCORRECT (well in the tank its about an inch over the top line and stays there, so i think! and the dip stick is fine, smells fine, looks fine i replaced the tranny twice in my 97 gtp so i know what to look for and listen for so i dont think its my tranny, this is why i need to see if it is the TC cuz if it is then it will frig my tranny right?)
LOW OR UNEVEN CYLINDER COMPRESSION PRESSURE
CARBON IN COMBUSTION CHAMBERS
DAMAGED IGNITION COMPONENTS
THROTTLE VALVE (is what i thought it was from the start)
SHIFT LINKAGE
TRANSAKLE MOUNT
EXAUST LEAK/NOT SEALED

To better describe the reason im so serious, i drove 6 hour to buy this grand prix, dont make em like these models anymore, and at 54,000kms, prior owners were an older couple from kansas parked it in their garage, perfect condition, when i seen the for sale add i jumped on it, 2000 grand prix gtp 4 door fully loaded, but brown colour but that ok im painting it white. who cares it only had 54,000kms right? so now after 9 monthes of owning my dream car, at 87,000kms why am i having to replace all the parts i metioned earlier, im just mind boggled, i dont know anymore, ive read so much, heard so many opinions, i ve had enough and i want to get to the bottom of this stupid problem and finally get to enjoy my georgeous GTP. so this is why i came here, people seem just as obsessed with Grand Prix's as i am, so....here it is, i dont know where else to go, ive tried talking with people on some other Grand Prix chat site and they were total idiots who dont reolize how great and unique and fun this car really is. its Pontiac's leading car for some reason right? Best car ever, but high high maintnance. worth every penny!

see now guys, this is what im talking about, now you see how crazy this is driving me, like im obsessed with this car, all my money is in this car, i know i said too much but i really really need help, i know what everything is that i metioned and how to fix it, but which one is it? if i can fix this problem my gp would be perfect. its getting worst everyday, cant take it to the dealer cuz they frig ya, anyways if someone out there really wants to help me with this, it is very important to me, and im adding my mods next week so i need answers, BADLY! ill even pay for help at this point, all ive ever wanted was my grand prix growing up and now i have my second GP but its just not working out for me. ok ill shut up now, im just looking for some help. Thanks for taking the time to read this who ever did. and NO im NOT crazy! LOL

Feel free to e-mail me if you are willing to take the time to help a rookie,
grahamdavis@sympatico.ca

What happens if you get on it? Does it take 1st gear all the way out to about 5800RPMS or so? Does it shift into 2nd without trouble? (slipping, extra hard, extra soft, etc) If you can rev out to 5800 or so, then you probably don't have a clogged cat.

By the sound of it, to me, at worst you have an exhaust leak which *might* be throwing off an O2 sensor, or you just have an exhaust clamp coming loose on a worn exhaust. The stock PCM programming isn't exactly the best. In my mom's SE, the torque convert likes to lock up at seemingly the oddest times to me. It can cause it to bog...then I have to give it a decent bit of gas sometimes to come out. Really it doesn't sound too bad.

Just take a step back, too much research on what could be a simple problem (or not even one) can scare anyone. I wouldn't worry about it that much.

Jesse

thats what people said about my 97 gtp, i knew it was the tranny and people said that same thing, 3000.00 bucks later i sold it the screwed up tranny screwed up more in the car, so im just protecting my investment i guess you could say, bad luck is no stranger to me, lol, it shifts beautifuly when i accel hard, but say im going about 30 or 40kms, (canada) and then press the gas the rpm drops and comes back up and sometimes drops again, then she kicks in but it gargles, and its getting worst. but its got alot of pick up and go, if i punch it, she fly's like crazy and shifts great, its like i always have to really punch the gas to avoid the bogg down and gargling sound, noone can really seem to pin point the problem

So how long ago did you install the Intake? Did you disconnect the negative terminal on the battery for 20 mins after you installed the intake? I didn't at first, and I was driving a civic for awhile. Then I did it and car was good to go.

nope, dident say to do that, should i have

Yes! The PCM has to relearn that greater airflow. I ran at half power when I added an open 9" kn without doing the neg terminal. And it sounded like crap. Just disconnect that negative (black) terminal for 30 minutes, and then hook back up and see what you get.

holy s***, that could just be the answer to my problem, thanks alot bud, so just disconnect for 30 and thats it?

Yup. If you want disconnect it overnight, just remember in the morning you have to hook it back up before you go anywhere. Damn, you're in Canada! That's far from me, lol..1,400 miles.

yup way way up here, people livin in igloo's and everything, lol joke, people think can is so far and cold all the time its funny, anyways,ok BUT!i had this problem before the intake, not as bad though, now its getting worse, but ill try what you said, i hope you are right, what would be the symptoms of a TC bummed out?, im hooked on this TC thing since ive been told about it, cuz exactly what is happening to me is the sigh of TC, no?

Have you or do you know if its had a filter/fluid change on the tranny? I don't know much about TC and I hope not to, best of luck for my tranny!, but changing the fluid/filter may give some life back to your tranny.

yup, and only the best, and added alittle lucas for the first time seemed to make a diff at first, but now, major power loss, what about TV cable
or throttle body
know anything aboutthat?

TV cable? Throttle body, yeah I ported my stock throttle body.

Hey I don't mean to barge in on this but what you have described is perfectly normal. On my old GTP, an '01, whenever I put the car in drive and started moving, the ABS pump would turn on as a "check" to make sure its working properly. (I'm 99% sure). So don't ever worry about that.

I can't help you on anything else, just thought I'd answer that question. Good luck to you though, I really hope everything works out for you.

WOW MAN YOU GUYS ARE GREAT ON HERE OTHER GP SITES THE GUYS ARE A** H****, THANKS BUD, DAMIT YOU'RE IN DALLAS, NOONE UP HERE IN ESKIMO LAND WITH ME? LOL, CAN SUCKS

There are a few Canadians on ths site I'm a transplanted Can. myself living Texas from Thunder-Bay Ont. Chico.