Having problems with your 2004 Honda Civic ?
Code P2646 This code is showing up P2646 Rocker Arm Actuator Prf or Stuck Off. Can you tell me what thhis is.
Change your oil
I believe it has to do with the vtec functioning. At certain time in accleration during rpm range the valve timing changes and it is probably a sensor that detects rpms. you need to check with someone else though because I am not an expert on hondas, just understand the principle of how it works.
Repair Help & Product Troubleshooting for 2004 Honda Civic
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