I recently finished a b16 swap in my ef civic. Once the engine reaches full operating temperature it starts to idle lumpy, like a rotary. Then, while driving it will hesitate and misfire between idle and 2500 rpm under load. I have an HA motorsports chip i recently installed to delete the vtec pressure switch and ELD. I am using a PR4 ecu to run the motor.

UPDATE: The weather has gotten colder and now it only starts to do this after i have engaged vtec.

Also, side note:

the base map chip has the o2 sensor disabled as well and my car has not been "tuned" yet.

Thanks in advance for any input.

 

Bump for any input