Ok I have a few issues that maybe completely different from each other but here they are.

1) Whenever I am at a constant speed, although more noticeable at lower RPMS the car seems to be missing, also does this while not in a gear. (learned of this from emissions testing)

2) After the car is hot and shut off. It normally tries to stall upon restarting the car unless I get on the gas to compensate. After it runs for a minute it appears to stop trying to stall.

3) Hesitation, slight bucking at low RPMs when not accelerating. This might be similar to my first problem. If I am in very slow traffic and in 1st or 2nd and let off the gas to slow up, keep it in gear and then push on the gas some it seems to hesitate fairly bad. Only if I get on the gas fairly hard does it not happen. Maybe this is normal?

4) Probably has to do with all the above but it backfires about everytime I have to get on the gas and then off to inch forward in traffic. On my way home from work there is a stop sign that normally has about 10 cars in front of me so that should give you an idea of what I mean. I move up roughly a car's length at a time and just about everytime I get a pop. When I drive normally, getting RPMs up higher and quicker this very rarely happens.

Relevant mods:

Pettit hi-flow cat
Pettit ECU
RB duel cat back
M2 downpipe
Stock airbox mod+K&N filter

Plugs were changed less than 1k ago
02 sensor, gas filter, plug wires, were changed last summer and probably have about 3k on them.

Any help would be great.

 

why kind of plugs are you using now?

could be the tps?

 

standard NGK plat plugs. 7s and 9s.

 

Ground(s), T.P.S. or partially clogged fuel injectors are where I would begin. However, I'd also PM rynberg and nicely ask for his suggestions, as well.

Mileage? Sudden problem? Intermittent?

Post your fix. Thanks.