Hi everyone. I replaced the VTC actuator on my 165K miles 2012 CRV. A day after putting it back together the engine light came on and it was for cylinfer 4 misfire. I've since verified timing, replaced the timing chain, tensioner and guides. And still it misfires on cylinder 4. I did a compression test and found that cylinfer 4 is at around 130 and the rest at 191 when dry. Then wet compression test cylinder 4 is at 165 and all others at 121.

I've swapped coils and plus and the misfires stay on cylider 4. I don't have the equipment to do a leakdown test. But was wondering if anyone had this issue after replacing the VTC actuator. I found on another forum that someone mentionef thst a honda tech didnt notice a "small piston on the VTEC came lose on the valvetrain and they adjusted and it fixed" not sure what they meant. Any help is greatly appreciated.

 

Update, just checked the rocker arms on the intake side of cylinder 4 and found they are locked in VTEC mode. All others are unlocked and running on the LOW RPM lobes. Took camshaft off and found the spring and small piston laying under the rocker arm. Put it back together and now it is fixed. This thread can be deleted my moderators if not needed.