So my CEL came on 2 months ago due to a bad O2 sensor. The knock sensor code came back as well. I replaced both and reset the CEL and it has not been back on again. Before the change I was experiencing alittle hesitation in the higher gears. After the o2 and knock sensor were replaced I thought it had gone away. but while driving yesterday i noticed the same hesitation. not as bad but it was still there. Any Ideas as to what this can be?

 

Is it only at high speed? Maybe a clogged fuel filter...

 

u sure ur knock sensor was bad? when you o2 sensor kicks in, it will also trigger your knock sensor. anyway, check your ignition coils.

 

Yep check coils, also. Try putting the ecu through its relearn cycle.
1) Warm engine to operating temp.
2) Disconnect battery until the clock resets.
3) Start car. DO NOT TOUCH ANYTHING ELECTRONIC. Let the car run for 5 minutes.
4) Turn car off, then take out the key. And your done.

Pretty much, from what i understand, the ecu records data all the time, to create an average.
This is setting your baseline idle to ideal conditions, with no loads, radio, windows going up and down, etc.
I know it works, or at least helps.
Good luck

 

fuel filter, did you change all three of the 02 sensors? just want to know for reference.

 

only the front right one thats the only code that came back other than the knock sensor.