Vtec troubleshooting....My vtec is not working at all i have a sohc zc with z6 head. I dont have o2 sensor or knock sensor hooked up. I dont know if they would cause vtec to not work or not. I have a p28 ecu with rywire conversion from obd0 to obd1 and the vtec harness from them. So wiring is done correctly. I'm just trying to figure out what would cause vtec to not work so if you can give me some suggestions so i know what to look at when i wake up it will be much appreciated thanks. good night

 

Is any O2 sensor hooked up?

Are you throwing some codes?

Does the car run? It must be since you can tell Vtec is not working.

 

I never took off 1 wire o2 sensor but the p28 can't read that i just dont have the money to buy a new o2 sensor right now got to wait till the 15th. Yea car runs good no limp mode or nothing. There is CEL on because of o2 sensor and knock sensor. Could be for more but i dont know because it doesn't blink like the obd0 one did. I miss that...i got to get it diagnosed. I just read the haynes manual and figured out how to check the vtec solenoid so im going to do that in morning. Also i know i took plug out of the block where it needs to be removed. But for some reason there was a bolt in the head. Is there supposed to be a hole that you can have a bolt in or not in the head. I didn't see it in haynes manual. It looked weird had a whole bunch of washers on it. Anyone with z6 head know what hole im talkin about?

 

o2 sensor and knock sensor would definitely disable vtec unless your computer is programmed not to look for those.

 

Is the knock sensor above the oil filter on the back of block with a red and yellow wire anybody can confirm this?