Recently built an all motor D16Y8. I got it tuned not too long ago, was running superb. A few days ago after I hit VTEC, there is a slight misfire in low RPMs, most pronounced at 3K RPMs and lower. I have a Stage 4 Camshaft, so it has a pretty lopy idle as is, now it wont even idle due to the misfire. It will clear its self up eventually if I disconnect the VTEC Solenoid or never cross into VTEC. I am clueless on what could cause it unless there is a VTEC Pin or something getting suck in one of the VTEC rockers, leaving only one or two cylinder stuck engaged. Any insight would be helpful and appreciated.

 

I would start by checking which cylinder or cylinders are missing. Check Spark plugs and wires. Spark plug wires with over 10000 ohms resistance will cause a low rpm misfire.

 

sounds like one or two cylinders are in fact getting stuck in vtec. Maybe try replacing the entire vtec solenoid assembly, as it may be getting stuck open slightly. Or as you said, some pins in the rockers might be sticking.
Or, the vtec lobe base circle might be too big. I've seen that happen before from a certain cam company. If the vtec lobe base circle is too big, there will always be tension on the pins in the rockers once vtec has engaged which makes them not capable of retracting back and unlocking when vtec shuts off.

 

Okay thanks for the replies, maybe its the camshaft then. I have a Stage 4 cam from Schneider Cams. Its pretty gnarly. I did some tinkering and I cleaned up the solenoid and replaced the filter/gasket. solenoid, I am having more of a random misfire is seems, it bounces around on the cylinders. I dont know if its a VTEC problem but it all started after a hard pull into vtec the first time. I am suspicous of possible headgasket failure. I am thinking of pulling the rockers off and giving it a good clean and to check and lube up the pins.