Hello new cl owner here, I'm hoping someone can point me in the right direction. I have a 2003 cl type s 6 speed with header j pipe high flow cat stock mufflers, intake 145k. The car seems to run good and has been a rocket ever since I got it but it just started to hesitate sometimes when in vtec and full throttle.

The service engine soon light came on shortly after I noticed the first hesitation. The service light has been flashing upon startup for the last couple weeks. The person who sold me the car said the service light flashing isn't something to worry about and that it was an easy reset.

It seems like maybe the car isn't getting enough fuel?. I recently replaced the fuel pump relay.


I have also had an intervention check engine light code for o2 senors (I believe p0420) a couple months ago due to possibly the high flow cat but the engine light turned off after driving it a few times. It still seemed to run good even with the code.


Could the high flow exhaust be throwing off a sensor causing my car not to perform?


Can anyone please shed some light!

 

If both o2 sensors are original to the car with 145K miles, replacing those would certainly help.




Also check your oil level. If it's low, its been known to affect vtec functionality.

 

It was the oil! It turns out my new ride likes to burn a little oil when in VTEC. I checked it when I got it a couple months ago and it was fine, I just recently checked it (after lots of VTEC) and it was about a quart low. I added a quart and it runs fine!