2000 GP GT Chugging when Driving up a hill

I have a 2000 Grand Prix gt. The car seems to chug and loose power when I drive up a hill or slowly pass somebody. I need help to fix problem. Thanks

Sounds like its not downshifting.

Is the SES light on???

SES light?

Service Engine Soon or aka check engine light.

The light is not on. the car runs great other than this problem but it seems to be getting worse. I plan on changing the plugs and wires. could this be the problem?

How many miles on your 2000? Last time serviced? Plugs, wires ect.?
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I just bought the car it has 63,000 miles on it and I dont know about anything else but I have bought new plugs and wires and will be putting them on within a couple days. and I have already changed the fuel filter.

Let us know when you get them in. Also there are a lot of post on this fourm on how to get to the back plugs.
Good luck and Merry Christmas.
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