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no power temp climbing

lostscout

lostscout

New member
Hi everyone

I desperatly need some help

2002 Gran Prix, 3.8L non supercharged

total lack of power...high idle (1300 rpm).....seems like any grade or hill...and I can't keep the speed....transmission kicks down, but engine loses speed...no power.....has slowed from 60mph to as low as 30mph

new spark plugs (bosch +4s) and airfilter about 6000 miles ago

power problem seems more recent......

changed the gas filter last week thinking that was the problem....no change

I haven't been getting a code....but checked and found po404....egr valve......changed the valve...cleared code.....

no change problem continues...and code returned


ideas please?
 


First off, get those platinum plugs out of there and stick some stock Irridiums in it. These cars hate platinum plugs and eat them. Did you change the plug wires when you did the plugs?

Beyond that, could be a clogged cat or a vac leak, or both. You didn't say how many miles are on it so that may help us.
 
The decel and lack of power makes me think the converter is clogged.
Plugs won't make a difference in idle speed.
 


132000 miles
plug wires are as far as I can tell original

now getting a idle surge.....
yes did cel flashing

tune up...plugs airfilter,,,about 3000 miles ago
 
change the plug wires. see if that helps. if not it could be a clogged cat.

only two thing make the light flash. need of a tune up, or clogged cat.
 
Hi Scotty just wanted you to know the major demon has been cleared....it went like this.......catalytic convertor was plugged....caused extra hot backflow thru egr, which burned a hole in the upper plenum causing a vacuum leak.....I got suspicious when after changing the cat con, I still had really bad surge....changed throttle body gasket...no improvement....could just barely get it running had a buddy listening under the hood, and found I had another intake leak....the burned plenum.....patched it (the 2 holes were fairly small) with JB weld it's working very well now...back to pre plugged convertor in terms of pwer and running quality......still getting engine code PO405 and 404....more to work on

p.s. egr valve is new also...about400 miles on it
 
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just wanted you to know the major demon has been cleared....it went like this.......catalytic convertor was plugged....caused extra hot backflow thru egr, which burned a hole in the upper plenum causing a vacuum leak.....I got suspicious when after changing the cat con, I still had really bad surge....changed throttle body gasket...no improvement....could just barely get it running had a buddy listening under the hood, and found I had another intake leak....the burned plenum.....patched it (the 2 holes were fairly small) with JB weld it's working very well now...back to pre plugged convertor in terms of pwer and running quality......still getting engine code PO405 and 404....more to work on


p.s. egr valve is new also...about400 miles on it
 
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Hi Reptile
just wanted you to know the major demon has been cleared....it went like this.......catalytic convertor was plugged....caused extra hot backflow thru egr, which burned a hole in the upper plenum causing a vacuum leak.....I got suspicious when after changing the cat con, I still had really bad surge....changed throttle body gasket...no improvement....could just barely get it running had a buddy listening under the hood, and found I had another intake leak....the burned plenum.....patched it (the 2 holes were fairly small) with JB weld it's working very well now...back to pre plugged convertor in terms of pwer and running quality......still getting engine code PO405 and 404....more to work on


p.s. egr valve is new also...about400 miles on it
 
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