GREETINGS ALL,
HELP HELP HELP. I HAVE A 1999 HONDA CIVIC EX THAT I PURCHASED IN MAY OF LAST YEAR WITH 14K ORIGINAL MILES. AROUND 40K MILES IT STRARTED THROWING A P1259 CODE. I REPLACED THE VVS VALVE ASSEMBLY. NWE SWITCH AND SOLENOID FROM A REPUTABLE ROCK AUTO BRAND. NOW VTECH IS WORKING INTERMITTENTLY AND SHUTS DOWN WHEN VTECH IS ENGAGED PASSING 95MPH. I HAVE ALSO REPLACED THE ECU AND HAVE CHECKED ALL WIRING. THE FACT THAT IT ONLY SHUTS DOWN WHEN PASSING 95MPH HAS ME STUMPED. PLEASE HELP!!! THANK YOU FOR YOUR TIME AND CONSIDERATION.

 

First, turn your caps lock off.

To confirm, you've replaced or made sure that the VTEC solenoid filter is clean, right? Are you still getting the P1259 code?

Check to confirm that your engine is, in fact, producing adequate oil pressure if you haven't already. You should also be getting 12V at the VTEC solenoid assuming the wiring is working correctly.

Edit: I did a search and found this post, which looks like it would be extremely valuable to you. Detailed troubleshooting procedure - https://www.civicforums.com/forums/1...ml#post2611612