I just got back my gsr with a b20 with a mildly built gsr head with a new head gasket. Well Its throwing a check engine light, but I think thats because my speedo went out. Ok my car hits vtec sometimes, and when it doesnt it boggs like its getting way too much fuel, but I also noticed on my SAFC when it boggs the Vto comes on to switches to "on." I'm pretty stumped...help!! Thanks.

 

possibly coolant temp sensor

 

Could be a number of things. Check your code or codes first. That'd be where I start.

 

get your speedo fixed,unless its been disabled the ecu should not let vtec enguage if it doesnt see the speedo working