I have a '97 2.2CL with the F22B1. 198,000 miles.

The headgasket blew after I had a severe coolant-leaking problem issue. After a grueling two days, I replaced the head gasket, radiator, thermostat, and water pump. I decided while having everything apart I would also change all the belts. Good as new. I even checked to make sure the head wasn't warped, everything went back together swimmingly.

It started up fine and seems fine (although the belts make an obviously different noise). I got to around 400-500 miles and decided I was through my own defined 'break-in period'. I noticed that the VTEC wasn't engaging. I know this because the engine has an obvious lull at any RPM over 4,500 and won't rev higher than 5,500 while under load. However, the VTEC operates fine while the engine is warming up and only seems to stop working once the engine has found it's comfortable operating temperature.

I checked my oil level and added to the maximum line, just in case. No dice. I checked all the connections to the head and the wires around it, but everything is connected the way it should be. I never unbolted the VTEC solenoid, so I doubt it's and issue. The harness is connected firmly. I even tested this by unplugging it, which did, finally, throw a CEL code. I reset the computer and plugged it back it and it didn't throw a code.

Anyone have any advice? I've spent the last few days scouring the internet for similar problems, but can't seem to find any applicable solution.

 

A bit more info:

After starting the car after it is already warmed up, the VTEC will work for a couple of minutes, then cease to work again.

 

have you checked the oil level? maybe the the oil is cold and thick its enough to engage the vtech but when it gets hot and thins out its not enough to kick it in. If its a little low sometimes thats enough to stop it from kicking in