Vtec solenoid wiring

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cycloneb18c3

Senior Member
I have a PR3(obd-0) in 91 teg. and I cant get rid of a CEL for code 21(vtec solenoid). I checked the wiring, and even rewired it and it wont work. could the 2nd o2 sensor wire not being connected be the problem?
I checked the vtec solenoid by jumping it to direct 12v and it works(clicks). I jumped it at the solenoid, and back at the ecu, all works. So the wiring is good, solenoid is good, but Ive tried 2 PR3's and I get the same CEL, so It has to be something on my car...?
 
have you tried manually engaging vtec i.e. driving with the vtec solenoid connected to +12v?

even on crap B16A1 cams, you should be able to feel a significant difference between the vtec and non-vtec lobe. You may indeed have a bad vtec solenoid despite it "clicking."

You should get a copy of the UK 91 CRX supplement to the helms manual. The PDF explains how to check the vtec solenoid i.e. resistance, etc. but I don't remember off the top of my head. I believe the Honda UK website has this PDF still. If not, post back up here and I'll find a link.
 
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the vtec works, I hooked it up directly to my vtec controller, and it works. I hook it up to the ecu and I still get CEL. The solenoid is good. I was wondering if having the 2nd o2 sensor disconnected would cause it. I have it disconnected, because I only have 1 o2 sensor in my header. the wire is good into the ecu---the popped open ecu cover and checked the pin(jumped it to 12v) and the solenoid clicks, so I know my wiring is good into the ecu. it does it on 2 pr3s- one chipped, one stock.
 
you said "vtec controller"
I bet $$$ that you have a wiring issue between the ECU, vtec controller and solenoid. remember, with a vtec controller yoiu go ECU -> controller and then controller -> solenoid otherwise you get CELs
 
I also tried running the wire directly to the ecu. still dosent work.
what I did for vtec controller, I wired pink and purple, vtec solenoid wire all together. that gives me vtec.
ok just vtec solenoid wire to ecu----no vtec
Im going to try and splice the o2 sensor wires together to run off of 1 o2 sensor(yes I know, Ive read hondatas website, but If the CEL goes away, Im going to have to get another o2 sensor)
Does anyone know what pin on the vtec pressure switch is ground and which one is positive? I looked in my helms manual and it wasn't too clear.
:blink:
 
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