Frustrating problem- please advise.

[samtheman77]

This is a 2003 altima with a 3.5L. When the motor is cold it idles fine and even drives fine. Once it is all warmed up, there is no more acceleration, the car crawls when you accelerate and never stalls. You can hear a funny noise from the motor like its not running on all cylinders when warmed up. O2 sensors were all replaced, all closed loop when warmed up. Exhaust was replaced, new cats installed.

This car does not have a module, they are independent coils (direct drive) on each plug wire. What could be the problem, plugs, wires, coils???
The plugs are NGK platinum and they do have black carbon on them but how should some carbon affect this, many other vehicles function fine with some carbon on plugs.

Suggestions?? Scan tools says both p0300 (general misfire) and p0301 (misfire in cyll 1) I did replace the plug wire in cyl 1 and no effect.

Should I clean TPS, replace plugs? ???

Any help appreciated.