Well i need help!

Im running a Y7 motor with a Y8 harness, and y7 ecu.

when i crank it, it idles and if i dont push the gas it cuts off!

Im thinking its the iacv, because the y7 has a 3 wire, and the y8 harness only has 2 wire? please help!

 

check for any restrictions like fuel delivery check to see if your fuel filter isnt clogged check you idle air control valve make shure your not throwing any codes check your timing if your off a few teeth your engine will not idle....

 

ok, my y8 motor is getting rebuilt, i got a y7 ecu, instead of the y8, and not it idles funny!

 

You know your problem....you've already stated it.

You have exactly one option - run the correct ECU/wiring harness/IACV that are meant to be run with one another.

3-wire IACV's will NEVER be controlled by an ECU meant to control a 2-wire IACV and vice-versa - no exceptions.

And if you thought unplugging the 3-wire IACV would help - it won't. 2-wire and 3-wire IACV's operate totally different and behave differently when they are disconnected.

2-wires shut down, effectively sealing off the air passage to the manifold.

3-wires do NOT shut down but stay open and DO allow a straight shot of air into the manifold.

 

the problem is that the y8 rev limits at 5500 i guess because the vtec isnt hooked up.

Ok, do i have to swap my whole intake?
can i keep the y8 manifold on the y7 motor

or if i put the y7 throttle body on with the iacv there, and run a wire for the third wire from the ecu to a three wire plug for the y7 throttle body?? do you think that wil work?

 

your engine will still run w/o vtec, just run the wires correctly to your iac and make shure your map and tps are connected or working properly, u will need a pinout diagram for that ecu......

 

and yes u can use that manifold for your head just make shure the throttle body seats correct because some throttle bodys have a diff shape than others causing a vacuum leak but in this situation it might not be the case but u just never know. also just to be shure check your wire firing order make shure that is correct and check the inside of your distributor make shure the rotor isnt loose i have had that happin to me b4..

 

ok i got the same prob see i got a LX motor but i got a EX wiring harness wit a EX ecu at 5500rpm it shuts down, i think its the vtec tryin to kick in, so i plugged a LX ecu into it and the LX ecu wont hold idle it jsut dies, i think its the iac valve only prob is cant figure out where the iacv is on my motor

 

I THINK THE IAC IS IN YOUR GLOVEBOX HAAA NO MAN ITS BEHIND YOUR INTAKE MANIFOLD, U NEED A HONDA BOOK OR READ SOME MAGAZINES OR SOMETHING ,ILL SEND SOEMONE OVER TO FIX IT FOR YAH HAAA JK..