Pontiac Firebird 1967-2002 - Need help with firebird

ok i have a buddy that has a 2000 firebird auto with 54,xxx miles on it and it has a hesation when the motor warms up to temp and does not go away he has had simliar problem before but it was much worse and undriveable it was the coil. He replaced 1 coil and plugs and plug wires with all brand new ac delco parts now he has a very slight hesation again but is loseing a good bit of power to be out run by a civic ,but still driveable and now he has replaced the fuel filter hoping that was it but no luck also we have misted water on the wires hoping it was a plug wires might arch off some thing and the car has never flashed a code and has been checked two times and hes about ready to run the thing in to the river :bang:

Might check the o2(s) symptoms sound similar to one going bad, it may not be bad enough right now to throw a code, but it sounds like it's getting close

A full diag would be best. I'm tempted to point toward the TPS. Since the throttle is not mechanical (throttle by wire), any issues there could lead to "hesitation".

Even on my old '84 T/A, when the TPS was getting flaky there was a "flat spot" on the gas.

Just a thought.

If it's only a "hesitation", and not a problem at idle or WOT, then it's not likely to be fuel or spark I wouldn't think.

it does not do it at idle but it does do it at anything off idle

"at anything off idle"? What do you mean? Is it lack of power, or is it a pause before responding (hesitation)?

Sounds like TPS or another throttle body sensor. I had similiar problems after swapping in a new TB in my 94 TA. There was no code thrown and it had problems with hesitation and idle surging.

It was the IAC sensor or TPS sensor (can't remember which) that was causing the problem according to my dad (mechanic). It was an easy thing to fix.

sorry about that no it doesnt pause when you take off its more a loss of power at any rpm, it takes a while to get rpms up to the shift point

My car is doing the same thing, except it spits black stuff out of the exhaust when it starts hesitating.