Ok,
Heres the deal people... My friend has a 92 Si Prelude with 4ws(4 wheel steering). It came with a five speed h23 motor... We swapped an h22 into the car about 2 months ago, we retained the factory h23 tranny with an act clutch. We also used the stock p14(h23 ecu) to run the motor and an msd switch to activate vtec. We also used a factory h23 harness. Now the switch has a 4600rpm pill in it so vtec kicks in at 4600. Since we were using an h23 ecu and the stock redline was 6500 on that ecu, for a while the powerband was just from 4600 to 6500. We then figured since it would be really hard to locate a jdm p13 with 4ws, we could just chip the p14 with an h22 spoon chip and raise the redline and all that stuff. Well, we did that and the motor still redlines at 6500rpm. The a/f ratio seem like they are working right on the motor but the redline still sucks ***... At first we thought the chip had problems so we tested the p14 ecu on an h22 accord, the car ran fine and was redlining at 8500rpm which was what the chip was meant to do... We also tested a p13 ecu on my friends prelude and it was still redlining at 6500rpm..which is way below stock... Does anyone know what the problem could be? I think something is not wired right... Maybe a sensor is not wired right? Oil pressure, knock sensor?? Or does it have anything to do with the fact that h22's are dual stage intake manifold's and the switch only activates the primary runners?? any help would be appreciated...thanks

 

I am having the same problem with mine but even when you put a p13 ecu in it does not work so i use a h23 ecu with a apexi vafc setup still cuts off at 6500 tell your friend that he should either go stand alone or hondata with a p72 or p28 ecu I am going with the hondata i will get back to you and tell you if it went ok

 

hey, i fixed my problem... We switched to a p13 ecu and rewired it... I took off the msd switch...the problem was the vtec oil pressure(on the solenoid) wasnt wired up, there are two green plugs on the vtec solenoid, you have to get the plugs off a vtec wiring harness and wire them into the wires that run to the ecu, its a five minute job..u probably need a wiring diagram

 

Hey, i had my wires hooked up to the vtec solenoid the there are three wires right one is ground and the two go to the ecu through the engine bay wall and i keep coming up with same problem fried two ecus already and yes i disconnect battery when putting on ecu i just dont understand should i just go with a whole h22 harness will that work since it is a jdm motor please help

 

it will work, but you need to switch around plugs. since the car is wired for right hand drive, all the plugs should be reversed.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Turbolude22 &raquo;</TD></TR><TR><TD CLASS="quote">Hey, i had my wires hooked up to the vtec solenoid the there are three wires right one is ground and the two go to the ecu through the engine bay wall and i keep coming up with same problem fried two ecus already and yes i disconnect battery when putting on ecu i just dont understand should i just go with a whole h22 harness will that work since it is a jdm motor please help</TD></TR></TABLE>

You have a short somewhere if you are frying your ECU. That is very strange.

Do you have the correct ECU fuse being 15A in the underhood fuse panel?

VTEC is 3 wires. Are you OBD1 or OBD2?

For OBD1, the wires are:

VTEC Solenoid to A4 (ECU input)
VTEC Oil Pressure to D6 (ECU input) and D22 for ground

HTH

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by poison &raquo;</TD></TR><TR><TD CLASS="quote">

You have a short somewhere if you are frying your ECU. That is very strange.

Do you have the correct ECU fuse being 15A in the underhood fuse panel?

VTEC is 3 wires. Are you OBD1 or OBD2?

For OBD1, the wires are:

VTEC Solenoid to A4 (ECU input)
VTEC Oil Pressure to D6 (ECU input) and D22 for ground

HTH </TD></TR></TABLE>

the ground doesn't have to go to the ecu. You can ground it at the grounding point directly below the vtec solenoid, where the harness itself grounds.

 

So wut do you sugges that i get a new harness does the usdm harness work on the jdm engine, also i dont think it could be a short since i have vtec when i use the current setup i use now the, the only thing is that my vtec cuts off a 6500 my current setup is h23 ecu and a apexi vafc controller do you think it would be easier to use a p28 ecu with hondata since i have a turbo already for the car fmax kit

 

use a p72 with a usdm wiring harness