HELP! 97 pontiac blowing smoke, not acclerating

[littleman2001db]

Hello,

weve been having problems with our 97 grand am pontiac for the longest time. It goes into random fits where it blows black smoke and wont accelerate past 30-35 mph until you floor then it eventully kicks up to speed. It also burns gas quick when it does this. No one can diagnose the problem. Weve replaced oxygen sensors and other things but it just doesnt seem to work. The weird part is that these fits are totally random and arent triggered by anything. Please help us with what this could be, weve been fighting it for years!

thnx

[98gpking]

Originally Posted by littleman2001db

Hello,

weve been having problems with our 97 grand am pontiac for the longest time. It goes into random fits where it blows black smoke and wont accelerate past 30-35 mph until you floor then it eventully kicks up to speed. It also burns gas quick when it does this. No one can diagnose the problem. Weve replaced oxygen sensors and other things but it just doesnt seem to work. The weird part is that these fits are totally random and arent triggered by anything. Please help us with what this could be, weve been fighting it for years!

thnx

this same thing happened to my trans am for about 7 months, then i demolished 2 pistons. so you might wanna check into it

[xeroinfinity]

Welcome to AF littleman2001db.

Has anyone done a compression or leak down test on the cylinders ??

Could be bad rings and when oil is spashed on the piston it drags excess up into the cylinders and burning it.
Could also be a partially cloged CAT Converter.

Good Luck

[jp_sdmf]

A friend of mine had the same problem a couple years ago with a 98 Grand Am apparently it was the cat being partially plugged.

[xeroinfinity]

Other thing, I forgot before, would be bad valve seals leaking oil into the cylinder(s).