I took out my ECU over night, put it back in to go to work this morning and now the car hesitates under partial throttle. It was fine until I took out the ECU for the night and then put it back in.

No codes, except for code 23 which has been happening for weeks and it's not related. Normally it throws code 23 and runs fine, so I am not leaning towards that as the problem.


I have 2 brand new o2 sensors that were installed with the new header over 3K miles ago.

Please give me some ideas.

The whole ignition system is new from the dizzy to the spark plugs.