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Exteemly sluggish

chezz

New member
Hey guys.. I've read a lot on here trying to see if anyone has the same trouble that I've had over the last few days.. I think I know what it is but figured I'd ask..

2002 GP GT 3.8 car has zero power right now.. no codes flashing

While at idle
she idles perfect, give it more than 2000 RPM and it'll start bogging bag and start running very lean.. sounds like it's almost starving for fuel or it can't exhale..

While driving.. zero power at all.. if I give it more than the 2000 RPM mark, it actually revs up but starts bogging bad and will not go past 4000 RPM, no bucking, and looses power and speed bad... It takes me about 1-2 miles to get up to highway speed and it's impossible to stay there when I come to a hill..

So far I replaced the MAF and MAP.. no change..
Checked air filter..clean.. actually pulled it off and no change either
Changed fuel filter.. lots of flow and pressure

I'm puzzled...

I'm thinking after reading other posts on here that it might be a plugged Catalytic Con. or a vaccuum leak..
What do you guys think

Rob
 


I am thinking cat too. If you have a vacuum leak usually your car will idle high and possibly not smooth. have you ever looked at the cat after you have rode in it for a while? Once you get back from driving it, get down and look at it. If it is glowing, then you need to replace it. How many miles on your car? Not sure on the specifics, but I heard that there was a recall on the cats in MY 00-02 if it has less than 120k on it. Not 100% sure on this though, just what I read in a different thread. Did this happen slowly over time? If it is the cat, get this thing fixed before it fails completely. If you think it may qualify for the recall, call your local GM dealer and ask if there is an open recall for this problem.
 
Thanks for the reply... the car has 142000kms on it
I did not look at the cat after I got home as I didn't realize or know what to look for..

This did just happen pretty quick.. I was on my way home from work and bingo, it started and hasn't stopped since..

I'm going to get the exhaust taken apart ahead of the cat when the service station opens again and then try it out... I don't have the gear here to burn the clamps off so I'll have to wait.but it's worth it to try..
 
It can still be bad if it does not glow hot, but if it does glow that hot, then there is a problem. Good luck though...if it is the cat and it is not covered by recall warranty, then this is a good time to get a new downpipe with or without cat. If you do not get a downpipe, get rid of the U bend atleast. You will thank me later.
 
I ask since I'm not very mechanically knowledgeable with these things.. what is the benefit of removing the "U-bend" ?
more flow?
 
Way more flow, more power. Its very restrictive. I GOT A UBEND AND CAT DELETE WITH MY DOWNPIPE AND IT DID WONDERS ON MY GTP. I dont see why gm made the gp with it.
 


Because it was a good spot for a o2 sensor and it was out of the way...factory doesn't mean smart...
 
I ask since I'm not very mechanically knowledgeable with these things.. what is the benefit of removing the "U-bend" ?
more flow?
yes. If you would like tons of info on our cars read the safely modding your 3800 thread in the general tech section........http://www.grandprixforums.net/f81/safely-modding-your-3800-powered-car-17482.html
This will give you a very strong base to start from as far as what each mods do and what order to do them, and just lots of good general info about your car/motor.
 
I had a similar problem with my Dakota once. There was a wire broke off the O2 sensor. It was dumping LARGE amounts of fuel in and trapping it in the Cat. After replacing the O2 sensor and putting a Magna Flow high flow Cat on it all was well again.
if you try driving your car at night, set up some ramps so you can get a good luck under it when you return. Drive your car right up onto the ramps (power permitting) and you will see it glowing if thats the issue. you can't miss it...
 
Took it for a very sluggish ride tonight and no "Glow".. plus a buddy of mine held his hand over the exhaust and said the flow seemed fine..

I'm stumped...
 


ied say its the cat the catalyst might have broken up inside of the case and lets eshaust by at ildle and up to 2000 rpms and when you put load on it or higher revs it cant push the exhaust through anymoreand it bogs it down I say its your cat
 
did you call the dealer? It could be under warranty and they will fix it for free....it will take you two minutes to call them.
 


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