2003 Grand Am GT has major power issues

live2racelive2race Member Posts: 3
edited October 2013 in Pontiac
I have a 2003 Grand AM GT 3.4 with 166,000 miles, its hard to explain but will try. When your first taken off the car seems like its holding back, but then once you hit 3,000 rpm's with the gas pedal still pressed the same amount the car takes right off like it has a power band. Same thing regardless happens all the time under 3,000rpm. Going down the highway at 70 and you start to go up a slight incline, you give it a little gas and you can feel the car having lack of power, then you press a bit more on the gas and it kicks down a gear and goes. Then back in the same situation once back under 3,000 rpm. The car idles normal, check engine light will come on once in a while, but goes back off.

Just put a new egr valve in today and seems like its doing it worse, could be my imagination. But here is a video. I just changed the o2 sensor and EGR valve, when i ran the code on the car that is what came up with issues. Its hard to here it in the video but the car is holding back, has no power as you can see on how slow the rpms are going up, and it is bucking bad when accelerating slowly.


when i unplug the egr valve, it definitely runs better at lower rpms taking off, but still same results as the video with the rpms not climbing fast, seems like the rpms will not get to 5,000 rpms when holding it to the floor as you can see in the video.


  • live2racelive2race Member Posts: 3
    i just removed the upstream o2 sensor and drove it for 10 minutes, hammered on it to see how it ran, it runs normal and rpm's climb right to red line fast. So that tells me one thing, Catalytic Converter is plugged. Im gonna cut the converter off and gutted or just replace it with a test pipe. Where i get my car inspected no worries there.
  • live2racelive2race Member Posts: 3
    Well i cut the Cat off today and replaced it with a straight pipe, the power the car has now is unbelievable!! i think the cat been going bad for a while, and just got worse. Cuz i cannot remember the last time my car had this much acceleration! Amazing lol
  • bensjetsbensjets Member Posts: 7
    I just bought this auto. Its loaded with all the bells and whistles. It didnt come with a key fob and Ive asked several dealers if it had one. It did, but they tell me it could be one of two that was made for this model. They wont give me any information cause they want to sell me one. Does anyone know where I can buy one and the information I would need to program it? I also checked with a few locksmiths with no luck. Its a 2004 Grand AM GT Sedan with a 3.4V6. The VIN # is 1G1JH12F527432140. Thanks for any help.
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