I had an B16A2 swap from a '00 Si in to a 97 hatchback with a 98 GSR ECU. They used my stock wiring harness and just added the necessary wiring for a VTEC swap. They had my car running but it was throwing out all kinds of codes; IAT sensor, MAP sensor and etc.... I took it back to the shop and had the wiring fixed. So, the codes was gone and my car was running good. But a week after that I was driving on the freeway and my CEL came on and it was throwing out Code22 - VTEC pressure switch. So I took it back again to the shop and they re-wired the switch ground wire directly to my engine ground and reset my ecu. I test drove it again and the CEL came back again on 5th gear @ 4,500rpm (90mph). This time they open up the whole vtec spool assembly and clean the oil screen and they gave me a new ECU. My CEL would still come on. I dont have a problem with my motor on 1st-3rd gear. 4th gear my motor will engage VTEC (4500rpm) but as soon as i hit 90mph my CEL would come and throw out Code 22. 5th gear my VTEC wont even engage as soon as I hit the VTEC point (4500rpm) my CEL would come on and throw out the same code. I've already have my VTEC pressure switch replaced, my oil pump replaced, and my ECU replaced, still having the same problem. I've talked to the guy that did my motor swap, he said its the wirings. But everytime I call him up to get my car done he never answer my calls and I left him a dozens of messages already. Can anybody give me an instructions how to check my wirings. There's nothing wrong with my wires, I've already test it with the multimeter and i have a voltage current from end to end of the wires.
Thnx a lot!!

 

I just recently started up a new swap and I got the same issue.

I looked thru all these threads so maybe they will do you some help:

https://honda-tech.com/zerothread?id=1034175

https://honda-tech.com/zerothread?id=984842

https://honda-tech.com/zerothread?id=769943

https://honda-tech.com/zerothread?id=225481

Turns out I didn't need it. I checked the vtec plug and it was broken in half and super glued together. Last time I get a swap off H-T.

 

got the problem fixed! turns out that the pin was halfway inserted, there's only a little bit contact on the wires.