JDM D15b 3 stage vtec help!!!!

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add404

New Member
wondering if anyone can help regarding the JDM D15b 3 stage Vtec. thanks
 
swapped my 1500 carb engine to the JDM D15b 3 stage vtec, the installers and i were in agreement that i would use my stock manual tranny, but the engine they installed came from CVT equipped EK, so the engine has auto ecu and intake manifold and head. they were able to install it, no cel codes, but when i took it home, had erratic idling, terrible gas mileage, and vtec seems not to be working. so first, tried to fix the idling, had IACV cleaned, including the TB, it eased up a bit but idling still erratic, but as of this the moment idling goes to 1500 rpm when gas pedal is pressed although when car is moving only. then everytime i switched the A/C rpm drops, then goes to normal idling around 800-900 then from time to time drops again, but no A/C normal idling unless braking as stated earlier.

2nd and 3rd is gas mileage and VTEC, i am thinking they are inter related? but not sure...

there, tried to be detailed as possible. can you help?
 
thank you for being interested.... hope you'll be able to help
 
Does your intake manifold look like this?

picture0373mo.jpg
 
If you're sure it was an automatic then you have the wrong IACV AND intake manifold. Automatic intake manifolds had the IACV on the throttle body I think.

attachment.php
 
Yup. You have the wrong intake manifold. The only way to fix the problem is to get a D16Z6 intake manifold or the D16Y8 intake manifold. And make sure its from a manual transmission.
 
thanks, changing the intake manifold will solve the idling problem?... how about the VTEC not working? how that can be fixed? thanks
 
It will solve the idling problem. If you look at the picture I posted above the finger points at the IACV blocked off. If you have that its wrong and you need a D16Z6 or manual D16Y8 IM.

Now for the VTEC problem....what kind of Honda do you have?
 
4th gen is an EF. So you have an EF or EG?

If you have an EG, make sure you have the right ECU. The motor you got installed uses OBD2 electronics and an EG uses OBD1 stuff. It's a huge pain the the arse to convert it to OBD2 so my guess is the guys kept the stock ECU in there. You need to grab the number off it. Passanger side foot well.
 
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You need a manual trans P2J ECU. You're going to need an intake manifold from a 99+ D16Y8 that has the EGR, and a throttle body from manual trans. You can use a throttle body from an EG but you might have to pull the mounting studs. In the pic that engine is missing the MAP sensor and TPS. You will need to convert your harness to OBD2. Then you will need to add wiring for EGR and for the dual VTEC solenoids.

You should take it back to the place that installed it and have them fix it.
 
All he needs is a regular manual Y8 IM. I'm running a stock Y8 IM on OBD1 right now.
 
my apologies but the generation i am not sure if its 4th gen but i am sure its a EG. i don't have a stock ECU because the stock engine is a Carb.

as to returning it to the mechanics that made the installation. i am having 2nd thoughts because our original contract (or understanding if you will) is that they gave a fixed price for the engine and installation; and when i inquired if they know the engine, they told me that there was going to be no problem, that it was only a D15, etc etc. so meaning they projected that they were experts. then it turns out that this the 3 stage was totally on a different platform. So they started proposing that i look around for IM but my own expense. that is where we started to have problems, when they couldn't fix the problems, they want me to spend again but which they gave no warning when we agreed on the terms at the beginning. sorry if this is too long...
 
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