obd0 obd1 wiring question im stumped!!!!

[civicdemon91]

OK own a 91 dx got a y8 motor just baught a p28 ecu an conversion harness now where do i hook up the vtec solinod an pressure switch to cuz i know the 4 wires hangin off the conversion harness are for the 4wire o2 sensor or am i wrong?Can any explain this to me please its spring an i want my beast to hit the streets lol

[Scott82]

Where did you get the jumper harness? The one that i used had 12 wires pigtailed out of it. I only had to use 8 of them but it had wires for v-tec and everything. Do they have a non-vtec jumper harness???? Maybe you recieved the wrong one. I'd look into it. contact whoever you got it from and if it came w/ wiring instructions see what it says. What color are the wires. Are the wires 4 differ colors?

[civickiller]

should have instructions

[Scott82]

Mine did. I can't figure out what jumper harness he has unless there is a non-vtec jumper harness but i am not sure about that cause i havn't dealt with anything like that. Civickiller, is there a non vtec obd0 to obd1 jumper harness that you know of. If so i bet that is what he recieved since all it seems to convert acording to him is a o2 sensor, cause other than the o2 sensor all i had to run were the vtec wires.

[civickiller]

no i havent heard of a nonvtec jumper harness but dont you only have to add a power wire and a ground wire for vtec ? 3 wires are for the 4 wire o2 sensor. if theres only 2 wires for vtec, then the 4th wire is for the power for vtec. and you probably gotta make your own ground.

now i could be wrong because i didnt do this before but just thinking about it alittle bit, i came up with that

[Scott82]

well the vtec solinoid is one wire and the vtec pressure is 2 wires. i don't know about if all you have to do is ground one of them.

[civickiller]

k well thinking about it even more

on the 02 sensor

1 wire is for you stock o2 sensor
1 wire is for you heated signal
1 is a ground
1 is a switched power source

so maybe if his conversion harness is ghetto, it could work like this:

1 wire goes to your stock o2 wiring
1 wire comes from the adapter for the heated wire
1 wire you gotta make yoru own ground
1 wire you gotta make your own switch 12v power.

so if thats the case then you only really need 1 wire from the conversion harness. maybe another wire is for the vtec solenoid and the another wire is for 1 of the vtec oil pressure wires ( the other should be a ground i believe) and the last wire for your knock sensor

[Scott82]

there is not a knock sensor on the d15 vtec

[Exempt]

And no VTEC oil pressure switch on some d15b VTECs either for that matter... Mine is one of the unlucky ones... Apparantly, its controlled by the ECU on the models not equipped, unfortunately Im using the P28 which dosnt control that, and actuall will look for one, so I have to rig it up so it wont throw a code on me... And I have to be carefull that I dont go into VTEC when I first start the car...

[Scott82]

The p28 controls the vtec pressure dosn't it. Mine wired up fine. I do have a check engine light on and i am not throwing any codes But vtec seems to work great and i havn't had any probs so far. My check engine light has gone off a few times but it comes back on after a while but the car runs the same either way