Code 21

[CB7 Fanatic]

I'm throwing code 21, which is the VTEC solenoid. I've seen A LOT of people on these forums that have done this swap only to have the same problem. I have not seen a solution though. I know the wiring is fine. The VTEC worked just fine in the donor car I pulled the engine from. What's the deal?

[cb9tuner]

when I did my swap I had that and other cels but for this one I did the usual check the wiring which you did already and you say its fine check if you installed the pin upside down I had it upside down giving me a lose connection and also check if the connector on the switch itself is ok and also check the oil level

[cb9tuner]

if everything passes repalce the solenoild in the end result I had a bad ecu causing all my cel's

[cp[mike]]

i know thats a very common reason why vtec doesnt activate is from a dirty screen(common after swaps, dirt gets loosened and makes its way up there), but i cant remember if that throws a CEL or not... if the ECU knows its bad, that usually means theres a problem with the wiring, or the sensor/solenoid itself.

remove the solenoid as well as the whole assembly, clean it out, and replace the gasket.

[CB7 Fanatic]

remove the solenoid as well as the whole assembly, clean it out, and replace the gasket.

Already did this when I did the swap. I'll check for the upside down pin thing tomorrow, but I think I was pretty careful not to do that when I put them in. Thanks.