I have a 91 crx si with a jdm b16a. I have done all the tests mentioned on this site to troubleshoot the vtec. The only one that I have not done is swap the ecu for one that I know has functioning vtec. I have a pr3 ecu. I have even hooked up a mechanical oil pressure guage on the port that sits near the vtec solenoid and driven it. At above 5000 to 6000 rpm the guage jumps up to about 75ps, which I believe is exactly what's suppose to happen. So is there any way to check this ecu to see whether or not it's good. By the way I get absolutely no trouble codes either. I would hate to shell out a couple hundred bucks on another pr3 ecu, and find out that mine is fine. Any help would be great.

 

do a search, and there is a list of stuff that you should try, try ALL of them, trust me.

also, check the VSS, back of gauge cluster.. that's what my problem was.. and the symptoms were similiar, good oil pressure, no ecu codes, no vtec, sometimes fuel cut @ 7200 rpm..

anyhow, it was a burnt circuit on the back of the cluster.. swapped out cluster, and bling. vtec