Anyone ever experience this before?

[born4music04]

When my engine heats up after some hard driving, at a coasting speed at around 3000 revs it will studder or hesitate. I'll let off it for a while to let it cool off and it will stop for a while but comes back. I think it might be something to do with the o2 sensor acting up and maybe messing up signals to the afc. Also, the check engine light came on right around the same time this started. The motor is almost brand new and just tuned and checked up. Any ideas would be great.
Thanks,
Cory

 

[crankbender]

When my engine heats up after some hard driving, at a coasting speed at around 3000 revs it will studder or hesitate. I'll let off it for a while to let it cool off and it will stop for a while but comes back. I think it might be something to do with the o2 sensor acting up and maybe messing up signals to the afc. Also, the check engine light came on right around the same time this started. The motor is almost brand new and just tuned and checked up. Any ideas would be great.
Thanks,
Cory

is your afsc monitoring o2s? if so disconnect it you don't need it to and it can leech signal and cause the ECU to see the wrong values.