94 Prelude H23a to H22a Conversion
I just installed a JDM H22a in place of a bad h23a, in a 94 Prelude Si. The JDM motor was a manual, and the Prelude is an automatic. I'm going to wire it up this weekend. Most of the plugs are the same but:
1. The distributor on the h23 has an external coil and the plug on the wiring harness to match it. The H22 has an internal coil. Do I just use the whole distributor off of the h23?
2. The fuel line on the h22 is on the right side of the engine, the stock line is too short. Do I buy a longer line or try to switch the fittings to feed the rail through the left hole?
3. I know that I need the p13-auto ECU, but I need to know which wires to run for the VTEC option. I heard it's 3 wires but don't know where to find a pinout on the "net".
Any answers fron somebody that has done this before? One company was going to charge me $250 plus shipping to convert my stock wiring harness! What a rip-off that would have been.
I 'll probably have more questions and some answers after I get it running. I finally got it all bolted in last night.
Wow that's odd, I'm just finished a JDM h22a swap into a 94 AWS lude today....
None the less, I'll make a "How To" list with detailed infromation as far as the pinouts and dist. plug goes and some pictures to help you out.
Expect my updated post around 12-1 EST.
As far as the fuel rails go, switch up the sides to run it left and use different banjo fittings to make it fit.
I swapped out my friends accord with an H22A Type-S and we just rewired the Distributor with the internal coil to the ECU and it works. Its got the coil and everything. Just rewire the harness to your preludes' harness.
1. use the h231 distributor and the external coil
2. use the h23a1 fuel rail and lines
3. use the 5psd ecu and the h23a1 tranny controller. run 2 wires
one to a4 and one to d6 a4 is your vtec solenoid and d6 is your pressure switch. then run a ground for the pressure switch.
Did you ever get those distrib pin outs?
Can you help with the pin-outs for the internal coil distributor? I think the wiring harness has 3 wires for the external coil. that would be a lot easier if I just have to move one wire to the distributor to get spark and not have to mess with re-timing it.
Thanks for the tips. I was able to use the H23 fuel rail and bolted it all together. Did you mean to get the 5speed ECU to use on my AUTOMATIC Lude and keep the auto controller? I don't understand. Another forum said to get the "p13-auto" ECU.
I plugged everything in except for the oil pressure sensor and the vtec solenoid. I had to change the throttle body side plate for the one with dual grooves, one for the gas pedal, one for the auto trans pressure valve. I did change the distributor, but would like to use the internal coil due to the vtec solenoid being in the way of the coil mount. I had to move over some extra emission valves from the h23 intake, and remove an extra solenoid control valve that controlled the vacuum to the fuel pressure regulator on the h22. I also had to use the h23's upper radiator hose neck, since the h22's neck didn't have a temp sensor on it.
I tried to start the engine and don't get any spark OR fuel delivery. I was told that I have to have the JDM H22 ECU installed or it will not run, So I tried that too. I don't hear the fuel pump come on when I turn on the key. It's back to troubleshooting 101. I'll let everyone know what I find.
Thanks in advance!
You can start the car with any ECU. OBD1 that is. F22, H22 USDM or JDM will start the car.
at the bottom is the pinouts for the ECU. The JDM one is exactly the same. For this, I assume you have a multimeter (voltmeter).
Find out what color is for what wire.
B11 = CYP (Cylinder Sensor) (should have a shield around it), connect it to the JDM wire harness that has the same color.
B12 = CYP Ground. Do the same with it.
B13 = TDC (Top Dead Center) (shield around it) Connect it to JDM harness
B14 = TDC Ground. Do the same.
B15 = CKP = Crank Sensor (shield oround it) Connect it to JDM Harness
B16 - CKP = Crank Sensor Ground. Do the same.
You can test your wires at the Distributor to the ECU Pin connector and it should beep (using continuity checker). The wires with shields on the JDM harness should go directly to the Distributor. (Use a sharp pin or needle to tap the wires on the distributor and touch it to the voltmeter and see if it beeps. If it's the same color, or if it beeps to the same wire on the JDM harness where you are doing the connection, you should be okay).
This is all done without using an exernal coil. Because the JDM is internal. Just pretend you are connecting to the coil instead of right to the Distributor, therefore you don't even do any wiring on the distributor. Just the harness.
If you only do your wiring on the harness. You know, the connectors where the engine harness connects to your cars harness. When you wire the Distributor pins from B11 through B16, it will be connected to the Coil internally already. No need to wire anything directly to the coil inside the distributor.
It's running BUT;
I finally got it running last night, but had to get a wiring diagram to find out why I wasn't getting any power. It looks like I dont have a ground point at my black wires. The dash lights up and the starter cranks, but I didn't have a good ground to the fuel pump and ignition. I'll trace the wires and see where they should go. Everything worked when the h23 was in it though.
I had to ground the BLACK wire on the fuel pump relay. I then had fuel and spark and was able to start the car.
The wiring diagrams show all the grounds going to a common point. Does anyone know where the common ground point is? This is the ground from ECU-A23,A22,fuel pump relay, some engine sensors, all marked BLK in the wiring diagrams.
I'll trace it with a "fox and hound" signal tracer tonight, but was hoping somebody has dealt with this before. The h23 didn't have any ground problems.
Which Distributor are you using?
Can I have the one that you are not using? I need one.
Thanks for your help 92H!
The distributors belong to the guy that I'm puting the engine in for.
I'm using the External one now, but will switch to the internal, when I find this damn ground wire.
Does anyone know where the 2 BLK wires, in the ENGINE Wiring harness, go to ground? These are also the shield wires that go around the distributor circuits. I can't find where they ground to either the battery or the engine.
As long as you have a ground wire from the car's chassis to the the engine. Just ground it to the engine. It'll work.
After looking for 4 hours, I found the 2 wires! After almost unplugging everything, I found the ground terminal under the thermostat housing. I just forgot to put it under a bolt when I installed the engine. I was able to drive the car after putting everything back together.
Where do you get 2 pins to plug into the ECU connectors for the VTEC and Sensor? I might have to get an old plug from a junk yard and butcher it for 2 pins.
Thanks for EVERYBODY's HELP. The H23 to H22 wasn't too bad!
If anyone else is doing the swap, I also had to change the front exhaust pipe. It goes from the jdm H22 Header to the cat. be sure to have one of these already or else you'll have to buy the pipe from an exhaust vendor. The H23 front pipe does not match the H22's header at all.
Anybody needing assistance, please e-mail me.
Phew, all sounds a bit over my head, but one thing I can contribute: don't get mixed up, a header is the combination of the downpipe and the a-pipe, what you meant to say is that the a different a-pipe was needed to connect the H22 downpipe to the cat-converter, lol, see, I'm smart too.
u will not have ANY vtec with the h23a1 ecu
the car will also not rev past 6500ish rpm
and will also not have very much power above 4500 rpms
im pretty sure you need a separate tranny ecu for the automatic transmission...
did u jump the obd1 service connector and extract the code from the ecu or you just saw the light was on and left it alone?
chances are it is something stupid and im willing to bet the ecu is fine.
an auto h22a will be extemely quick, prob not as quick as a 5 spd for lack of better gearing (4 spd auto)
but damn fast for an automatic 4 cyclinder, like low 15's or high 14's, 1/4 mile depending on tires.
89 DX hatchie
81.25mm hybrid stroker
it does alright from 5k to 9k
Everything in one post.
I had an e-mail from a user that couldn't understand all of the posts. From all of the posts above, I've put everything into one.
The rewiring of the distributor was only needed for the ACCORD swap. The H23 to H22 swap didn't need any pin mods at the distributor. I'm told that the car is EXTREMELY FAST and gets 3rd gear scratch!
1. use the h231 distributor and the external coil: It plugs right in to the stock harness WITHOUT ANY PIN CHANGES. The 2 external coil brackets are available from Majestic Honda for about $20.00 here. http://www.hondaautomotiveparts.com/...=IGNITION+COIL
2. use the h23a1 fuel rail and lines: I took the fuel rail off of the H23, and swapped it with the H22 to get the Fuel line to hook up.I also swapped any emission valves on the intake, to match the original wiring
3. use the P-13-AUTO ecu, if you are using an Atomatic like me. We got if from a dealer here for $175.00.
4. run 2 wires to the ECU. The end of the 1st wire goes to A4 on the ECU and the other end goes to the VTEC solenoid. The second wire goes from the ECU, pin D6, to the oil pressure sensor on the vtec head. The 3rd BLACK left over wire on the pressure switch, goes right to the engine block for a ground. We had to buy 2 different style pins to crimp on the wire ends to plug into the ECU, from the Honda dealer. The Check engine light was on till I added the 2 wires with the new ECU, but was able to drive the car, WITHOUT THE VTEC WORKING, with the old ECU.
5. I had to change the front radiator hose neck, because the JDM one didn't have the extra temp sensor.
6. Had to change the front exhaust pipe to hookup the exhaust.
7. The VTEC has a 6 groove pulley, the h23 had 5, so either use thinner belt or swap the pulleys.
The h22a auto prelude
The kid that I sold the car to lost control of the car and rolled it. Everytime I talked to him, he told me how fast the car was since I put that engine in for him. The whole thing was totalled except for the doors and wheels.
I just bought the whole Prelude Si with the JDM H22a for $1500. I kept the engine and interior and cut the rest of the car up and threw it in a dumpster at work. I also just bought a '93 Black Prelude Vtec with a knocking engine for $2500. So it looks like a busy weekend. This JDM H22a is going back into another 5spd Prelude.