2002 LX to 2004 EX head swap wiring
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2002 LX to 2004 EX head swap wiring
Hey guys I just bought a 2004 VTEC head and I was planning on doing a swap and I read some forums about doing the swap and I learn a little bit more each time but one thing I'm confused about is running the VTEC solenoid to the ECU. Im getting a EX ECU with a ignition module and a key that was originally used with the ECU from ebay. I really don't know how to run it. It's the only thing I'm stuck on. I need someone to really explain to me. below I have a diagram from a later forum but I couldn't find anything on how to wire it. Can someone help me out?
Last edited by RoseyEm2; Jan 27, 2017 at 05:43 PM.
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Re: 2002 LX to 2004 EX head swap wiring
The EX PCM needs to be for an 02 car (or 01-03) with the same trans as yours, if you wish to go that route. Your 2002 car cannot use a 04-05 PCM.
Running a few new wires to the PCM is one thing, but you're gonna need the correct connectors for the VTEC parts and you're gonna need some correct wire terminals to go into the PCM connectors. That's probably another trip to a boneyard to hack out some harness chunks.
Might be a whole lot simpler to get a standalone controller (google VAFC?) to run the VTEC solenoid....you could make it turn on whenever you want to.
(a toggle switch could do the same thing for about $3, you could label it "EJECTOR SEAT")
Running a few new wires to the PCM is one thing, but you're gonna need the correct connectors for the VTEC parts and you're gonna need some correct wire terminals to go into the PCM connectors. That's probably another trip to a boneyard to hack out some harness chunks.
Might be a whole lot simpler to get a standalone controller (google VAFC?) to run the VTEC solenoid....you could make it turn on whenever you want to.
(a toggle switch could do the same thing for about $3, you could label it "EJECTOR SEAT")
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The EX PCM needs to be for an 02 car (or 01-03) with the same trans as yours, if you wish to go that route. Your 2002 car cannot use a 04-05 PCM.
Running a few new wires to the PCM is one thing, but you're gonna need the correct connectors for the VTEC parts and you're gonna need some correct wire terminals to go into the PCM connectors. That's probably another trip to a boneyard to hack out some harness chunks.
Might be a whole lot simpler to get a standalone controller (google VAFC?) to run the VTEC solenoid....you could make it turn on whenever you want to.
(a toggle switch could do the same thing for about $3, you could label it "EJECTOR SEAT")
Running a few new wires to the PCM is one thing, but you're gonna need the correct connectors for the VTEC parts and you're gonna need some correct wire terminals to go into the PCM connectors. That's probably another trip to a boneyard to hack out some harness chunks.
Might be a whole lot simpler to get a standalone controller (google VAFC?) to run the VTEC solenoid....you could make it turn on whenever you want to.
(a toggle switch could do the same thing for about $3, you could label it "EJECTOR SEAT")
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But would it be easier to just run a VAFC than just doing the whole ECU swap?
(but I personally try to never do either of these)
Do your research first, check out options and see what suits you best.
And I have no idea how to wire it.
Seems like installing the standalone controller would be easier than installing a stereo.
Laying a couple wires of your own from the engine compartment to wherever you want to put that controller might be easier than trying to lay some the set of new wires to connect into the PCM harness, swapping the PCM and steering column lock and all that......then having to use multiple keys to get in and start the car.
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Sure seems to me like it would be easier if I were doing something like this in a driveway.
(but I personally try to never do either of these)
Do your research first, check out options and see what suits you best.I bet a vafc comes with some instructions. Google it?
Seems like installing the standalone controller would be easier than installing a stereo.
Laying a couple wires of your own from the engine compartment to wherever you want to put that controller might be easier than trying to lay some the set of new wires to connect into the PCM harness, swapping the PCM and steering column lock and all that......then having to use multiple keys to get in and start the car.
(but I personally try to never do either of these)
Do your research first, check out options and see what suits you best.I bet a vafc comes with some instructions. Google it?
Seems like installing the standalone controller would be easier than installing a stereo.
Laying a couple wires of your own from the engine compartment to wherever you want to put that controller might be easier than trying to lay some the set of new wires to connect into the PCM harness, swapping the PCM and steering column lock and all that......then having to use multiple keys to get in and start the car.
If you think a good mechanic is expensive, try hiring a bad one
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From: Midwest. Aiming about mid-chest
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I just wanted it to be done properly you know?
When I do wiring repairs in a car, I strive to make my work permanent and expect it to last as long as or outlast the car.
I have a wiring diagram from a VAFC2 on my phone and I have read some forums about it but nothing tells me how to run a wire to the VTEC solenoid and which wire it has to be on the VAFC. I know that the VAFC is gonna power the VTEC solenoid somewhat and tell it when it's time to engage. And I'm sure I'm gonna have to add a longer wire so it can reach all the way to the engine bay.
These things usually assume the installer is not a novice and has some experience so they don't have to print 20 extra pages covering the minutiae of how-to strip/solder/crimp/splice/route anew/seal/de-pin/re-pin/etc. These skills are very important to know BEFORE you approach a project that involves anything with wires.
Re: using another PCM:
Because there aren't already any of the necessary wires in the car for these new parts you install..........You would have to do just about the same work (but with more detail IMO) to electrically connect these newly installed parts that didn't come in the car originally, to a computer that also didn't come in the car originally, there are no instructions for this that were written by Honda, and that computer (PCM) will be a lot le$$ forgiving of mi$takes.
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"Properly" is in the eye of the beholder. Many people can make wires connect together and call it 'good', but it may not last very long and it may not be safe.....that's certainly not good enough in my book.
When I do wiring repairs in a car, I strive to make my work permanent and expect it to last as long as or outlast the car.You'll need about the same experience level as installing your own car stereo/alarm/remote start systems. Wire it up as per directions. Sometimes you need more info than what comes with the kit you purchased, like a wire diagram for the car.
These things usually assume the installer is not a novice and has some experience so they don't have to print 20 extra pages covering the minutiae of how-to strip/solder/crimp/splice/route anew/seal/de-pin/re-pin/etc. These skills are very important to know BEFORE you approach a project that involves anything with wires.
Re: using another PCM:
Because there aren't already any of the necessary wires in the car for these new parts you install..........You would have to do just about the same work (but with more detail IMO) to electrically connect these newly installed parts that didn't come in the car originally, to a computer that also didn't come in the car originally, there are no instructions for this that were written by Honda, and that computer (PCM) will be a lot le$$ forgiving of mi$takes.
When I do wiring repairs in a car, I strive to make my work permanent and expect it to last as long as or outlast the car.You'll need about the same experience level as installing your own car stereo/alarm/remote start systems. Wire it up as per directions. Sometimes you need more info than what comes with the kit you purchased, like a wire diagram for the car.
These things usually assume the installer is not a novice and has some experience so they don't have to print 20 extra pages covering the minutiae of how-to strip/solder/crimp/splice/route anew/seal/de-pin/re-pin/etc. These skills are very important to know BEFORE you approach a project that involves anything with wires.
Re: using another PCM:
Because there aren't already any of the necessary wires in the car for these new parts you install..........You would have to do just about the same work (but with more detail IMO) to electrically connect these newly installed parts that didn't come in the car originally, to a computer that also didn't come in the car originally, there are no instructions for this that were written by Honda, and that computer (PCM) will be a lot le$$ forgiving of mi$takes.
So If I use a VAFC2 will it power the VTEC solenoid at the given rpm that I programmed it to? Or would I have to turn on the manually each time? And I want to know how a VAFC2 controller would be simpler and is the best option.
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From: Midwest. Aiming about mid-chest
Rep Power: 518 Re: 2002 LX to 2004 EX head swap wiring
It's up to you to research and decide if the suggestion may suit your needs.
