2001 Accord H22A4 Build

l1nd3n

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Another update.
-Got T2W4 LSD trans. Came with JUN lightweight flywheel and shifter cables that I needed.
-Competed full 2.5" exhaust, with magnaflow cat and OBX twin loop muffler. It's still too loud so I got a vibrant ultraquiet resonator too. I'll post how it sounds after.
-Have the OBD2b to OBD2a conversion harness.
-Made plugs from my old f22b2 harness for the IACV and I can't think of the other thing now.
-Need to get ECU reflashed to match my immobilizer and then I should be ready for install.
-I do need new CV joints but that will wait until I have them out for a core charge rebate.
-Think thats it for now.
 

RawCarnage

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so question, since you got an obd2 engine would you be able to pass emissions with it? i have been wanting to do this on my accord(same year) but i never wanted to go through the odb1 route because of the whole emissions thing.
 

bairdandrew77

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^ depending on where he lives, he should be able to pass with very little trouble as long as the engine stays healthy, even with the higher compression pistons. If you use a stock healthy h22 with a stock usdm 5 speed prelude ecu (don't remember the ecu code for 97-01 models), you'll pass emissions no problem. Even with a jdm h22 or h23a you'll be able to if done properly. Again, depends on where you live.

OP, your car's thing to fly with that transmission. Hopefully you don't mind the high rpm on highways!
 

l1nd3n

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so question, since you got an obd2 engine would you be able to pass emissions with it? i have been wanting to do this on my accord(same year) but i never wanted to go through the odb1 route because of the whole emissions thing.

I am in the same boat as you. I live in Texas and don't have any connections to pass with obd1 emissions either. I will remain obd2. I did get a p72 ecu for future use but I'm in no hurry.

This is probably the hardest part of the whole build. I'll list what I know you will or at least what I will be doing to avoid check engine lights and to pass emissions.

-Get the ecu that matches the motor and trans your putting in your ride. Best to probably shop and get a motor already obd2, just a suggestion. The ECU I got is from an obd2 M/T prelude (p5m I think). Stick to the US ecu for emissions. Learn the ecu code your looking for before shopping.

-Get an obd2b to obd2a adapter harness for your ecu plugs to match the prelude ecu.

-Take the ECU to a dealer or locksmith with the ability to reflash your new ECU's immobilizer to match. Yes, it is possible and I was quoted at or a little above $100 from a local dealer and locksmith. The lockskith will come to the house for $125 and do it. I asked the guy if I have to start the car when he does it and he said no, just that the key will need to be in the on position. I am going in a few days to do this with my current f23 motor still in, I'll be sure to confirm.

-next, the wiring. You have to worry about the distributor, IACV and IAB.

-The distributor. The accord has a 4p plug and that's it. The prelude has 3 plugs: A 4p and a 2p on the distributor and a 4p plug (with only 3 pins) on the coil. So it's 4 prongs vs. 9 prongs. Well I belive I was able to figure that out last night and I will post up a decent diagram as soon as I double check it. Works out that really there are only 4 prongs (wires) that leave the area, the rest connect the coil to the distributor and/or power to the distributor icm or coil. Don't quote me on that yet, I will get this drawn up soon.
A jdm accord h22 4p plug distributor may work but not positive. After studying the wiring diagram of the US h22 coil and dist it makes since to me that it could work without getting a check engine light. Ok, next.

-You will need an extra engine wiring harness. Preferably the h22 but I got my plugs from a 96 accord harness. Accord is probaby cheaper too, if your just going to cut into it.

-From there you need to unpin your accord distributor plug and set it aside incase you decide to swap motors again someday. From there, I'll post a diagram soon...

-IACV is next. The accord has a 3 wire, the prelude is 2. One wire to ecu, one to a 15A fuse. I'll verify and post diagram soon.

-IAB secondary butterflies. 2p plug, one wire to ecu harness the other is power from somewhere. I'll let you know.

-I will also post my method of running and pinning the wires I used from the extra engine harness.

I am right in the middle of researching all this stuff so I can do this swap right in one shot with no or minimal issues. I'll try and get diagrams up soon. I have not found a decent obd2 h22 swap thread I can fully trust so I have just been going to the source, the service manuals, for electrical, specifically. Though I have learned a ton from other h22 swap threads, there just aren't that many obd2 ones for one, much less ones that go very far into the electrical side.

Hope this gets you started or a little more confident to attempt the swap. I'll hopefully post the diagrams soon. It is the holidays though so be patient with me please.

L
 
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I just finished my H swap and it is completely obd2 scan tool compliant. There are quite a few hurdles in the process and I had to pull info from dozens of resources to get it finished.

First find a prelude ecu that matches your evap setup. The preludes changed the evap design the last couple of years. I did 2001 p5m into 2001 accord.

Then satisfy all other emissions requirements of that ecu. 2-wire iacv, sensors on oil pump, vacuum controlled egr parts.

My ecu is a p5m-l54. I converted it to a 5spd ecu and installed an immobilizer bypass chip from doctronics.

I modified a spare accord harness for the swap and prewired the engine before installing it. I had to add a shielded wire into the harness for knock sensor, the shield runs to a common ground on the ecu side of the harness (brn/blk). The evap valve originally on the front of the intake manifold got moved to the underside by mounting it to an open bolt hole. I wired the IAB control solenoid into the harness as well. Once the motor was in I just connected the ecu using a obd2b to obd2a harness from rywire.

Since my car was a factory auto, the blue/white wire located in the connector under the fuse box in the engine bay had to be grounded before the car would start. I used this wire as a neutral safety input. When the car is in gear it sees no ground signal. Doing this will allow you to add a remote start without fear.
 

l1nd3n

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How to convert 4 wire 6th gen Accord Distributor to Prelude with 2 plug distributor and 1 plug Coil. This was my biggest hurdle in this swap. It took some time but I finally sat down and went over the wiring diagrams for both and now it's straight forward. The only wire not utilized is the blue one on the Distributor 2p plug, from what I understand the Tach gets its signal elsewhere. I'll correct if this turns out to not be true. I will also post something for the IACV and IAB soon.

Accord%2BH22%2Bdistributor%2Bwiring.JPG
 
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l1nd3n

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It's good to hear from people that have done this and kept OBD2 compliance. I just don't read of many doing it or many doing it and posting how they did it. It's good that people know what their options are. Like the Doctronics vs Reflash of Immobilizer. There aren't too many more options for OBD2 but at least there are some.
 

Ccrew95

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How to convert 4 wire 6th gen Accord Distributor to Prelude with 2 plug distributor and 1 plug Coil. This was my biggest hurdle in this swap. It took some time but I finally sat down and went over the wiring diagrams for both and now it's straight forward. The only wire not utilized is the blue one on the Distributor 2p plug, from what I understand the Tach gets its signal elsewhere.


Accord%2BH22%2Bdistributor%2Bwiring.JPG

Did this work for you? No check engine lights?
 
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