Anyone know anything about Grand Ams?

[BLACK KNIGHT]

Sorrry, know this isn't a Grand Am forum...but my dad's 2002 Pontiac Grand Am is having a weird problem. It has the V6 engine...I believe it's an SE model. He just had a tune up done to resolve this problem and it didn't help. The problem is the car has like no acceleration. When you floor it, it just accelerates extremely slow. The car has about 130,000 miles on it and it just recently started doing this. He had the plugs and wires changed and they thought it was a transmission problem. He took it to a transmission shop...I think Amoco, and they ran diagnostics and took it for a test drive (supposedly) and didn't notice a problem. But I'd say it's about as powerful as a 3 cylinder car. Any ideas???

[Transamman25]

Have the Cats checked .. 3100's ran through em almost as quick as the 4.3 vortec's

[LiquidFire350]

does it kinda sputter up, kinda like a misfire, or is it like a nice smooth slow accel?

[Transamman25]

Liquid a sputter up ? what are you thinking is wrong with it ? FP regualtor ?

[T'S95T/A]

Have the Cats checked .. 3100's ran through em almost as quick as the 4.3 vortec's
I agree 100% cats are pluged. Tap on the cat with a hammer and see if you here any rattling

[BLACK KNIGHT]

No, it doesn't sputter...it's just fairly smooth accelerating. The cat sounds like a good idea...it feels like it's choking or something. I tried flooring it and it just doesn't want to accelerate...no get up and go. He said when it sat for a week at the shop that it would barely do 20mph even flooring it. But now it will do highway speed it just takes it a minute to get up to 60! As you can imagine merging onto the highway is extremely difficult.

[LiquidFire350]

Liquid a sputter up ? what are you thinking is wrong with it ? FP regualtor ?
i was thinking kind of like a misfire problem, but he says its just slow moving

[BLACK KNIGHT]

i was thinking kind of like a misfire problem, but he says its just slow moving
The engine was tuned up (new plugs and wires) to try and correct this problem. I don't even see exactly how the transmission could be holding it back. It feels like the car surges slightly tho.

[Transamman25]

Take it up on blocks .. drill a hole before the cat and drill one after cat see if you notice a diiference in air flow coming out each hole .

[T'S95T/A]

Take it up on blocks .. drill a hole before the cat and drill one after cat see if you notice a diiference in air flow coming out each hole .
I don't think you want to do this, it will result in a exhaust leak. I would think there should be some type of flange between motor and the cat to disconnect. Depending on how cloged it is, take it for a long ride in the evening and look at the cat, if it is cherry red, it is pluged. Or take it to an exhaust shop. But this sounds exactly what happened to my truck and that was the cat.
Good luck let us know what you find

[Transamman25]

well after ya check ya simply weld over the hole .. but yes i worked for an exhaust shop in hs .. thats how we did it

[BLACK KNIGHT]

Dang, you guys are good!!! Blocked catalytic converter...new one welded on...problem solved! Thanks guys! You all rock!