Hi I have a f23a1 motor and throwing a 1259 trouble code. I check vtec solenoid and pressure switch and wiring all fine. Followed the FSM flow chart. Oil is full swapped out the whole unit. Engine idles rough and ant rev past 4000k rpm. Need help. Could a knock sensor do this. Sending a faulty signal ?.

 

First thing to check is wiring back to the ecu connector. Check for a dented oil pan.