just thought i'd post today's fix for a friend's second gen CRV. was told it was chugging and bucking at 2800 rpm but only with the AC on. after a couple hours checking google for AC bogging down the engine i actually took it out for a test ride and presto, there it was at the aforementioned rpm range. but it didn't stop when i turned off the AC. repeated it with and without the AC, no difference really. back to google after OBDII scan showed a code of P1259, vtec malfunction. could be several things, but one suggestion that of course i liked was maybe the vtec solenoid just needs to be cleaned. without knowing what exactly that meant, i took it off, not hard at all taking the 3 long 10mm bolts off but getting the wire harness holding plugs off the cover bracket was actually more annoying. there on the inside of the solenoid was a little microscreen fairly well clogged up with crud. i don't know the flow design for this system but it's obviously not coming directly from the filter given the buildup, i would guess. carefully pried the rubber gasket that holds the screen out of the body, sprayed the backside with carb cleaner, cleaned things up, reinstalled, test drive, problem gone away! the solenoid is fairly accessible on the back side of the engine, above the oil filter, it was about the only thing there and kneeling on top of the front grill area (with a rug under my knees) and sometimes with a knee on the valve cover it was easy to get to. i had looked at pics of the part online so i recognized it easily.