Post H22 Swap problems. - Honda Prelude Forum

mr. r00t · 03-26-2005, 11:20 AM

Hey guys,
Long time member and reader, kinda quiet on the posting side. I tried running a few searches, didn't really come up with anything.

A buddy of mine threw a rod in his H23, so he ordered a JDM H22. A nice mechanic at our local dealership owned a performance shop before working for Honda directly, so he said he'd drop it in for him. After the swap was finished, the mechanic is getting engine code 12, which he says is the EGR valve. He tried explaining that this is because of the JDM ECU/Engine conflicting with the USDM exhaust setup on the BB2, and that after diagnosing the problem for hours, he believes it to be a problem with the JDM ECU. He tested voltage and ohmage (is that a word? :>) and said one of the grounds D19 or something is discharging a bit of electricity when it shouldn't be. He also explained that when he puts the H23 ECU back in, the check engine light goes away, but obviously there would be no VTEC support then. This doesn't happen when you first turn the car on, just when you reach cruising speed on the highway. Also, turning the car off resets this, and the CEL stays off until you reach cruising speeds again. He also said that the Honda Tech Line they called didn't really have an answer for them. Being someone who owned a performance shop in the Harrisburg area (Tony from Modified, for you locals) for awhile, he suggested we try to pick up a USDM ECU and give that a go. This all makes sense the way he explained it, but you guys are insane monsters when it comes to knowledge on stuff like this, and I'm sure I'm not the first one to encounter this type of problem when dropping in a JDM H22. Can anyone confirm or deny the validity of his explanation to me, and suggest anywhere reputable to get a USDM ECU from (other than ebay, if possible).

Thanks in advance,
Jim

Lucke · 03-26-2005, 01:13 PM

when i finished my swap, i never threw a code 12. i'm not sure what if anything wasn't done, but you might want to check the whole EGR system. if its clogged, it will throw a code.

the code has nothing to do with the JDM engine/ECU conflicting with the USDM exhaust, because if it did, then i would have gotten the same code thrown.

clean out the EGR system then get back to us with an update.

mr. r00t · 03-26-2005, 01:34 PM

Mechanic said that he had tried the EGR valve from the H23 on there as well, with the same problem. I didn't know they were interchangable, but he said he used them both. He specifically said he tore the whole EGR setup apart to ensure it was setup correctly, which I assume would mean cleaning it up, too. Does the fact that the JDM ECU was discharging on D19 say anything useful?

Rudaluda · 03-27-2005, 07:07 PM

try checking out this PO.com write up, hopefully it will help

http://www.preludeonline.com/showthr...81#post1085281

neldogg · 03-27-2005, 10:53 PM

umm a JDM h22a has no EGR valve. and there is nothing on the exhaust system that would conflict

jsmooney · 03-27-2005, 11:35 PM

Quote:

Originally Posted by neldogg

umm a JDM h22a has no EGR valve. and there is nothing on the exhaust system that would conflict

Exactly... The just put em on there when they bring them into the US right? They also drill that hole through the head...

Honestly, you have two options. 1, try what the mechanic said. 2, block the EGR. Out of all the JDM h22a's I know... Over half throw a EGR code after the swap.

mr. r00t · 03-28-2005, 11:16 AM

Alright, I'll check that thread.

When you said half throw the EGR code after the swap, is that a permanent for good thing?

Edit: Thanks man, I read the thread. Didn't really approach my issue, but was informative none the less

So if the guy removes the EGR valve from the H22 all together.. would that fix it? Or can he not due that because the car is supposed to have one on.

aneurysm · 03-28-2005, 12:23 PM

Quote:

Originally Posted by neldogg

umm a JDM h22a has no EGR valve. and there is nothing on the exhaust system that would conflict

thats odd.....the ones I have seen, including my own, DO have an EGR valve.
And yes, a USDM EGR will function on the JDM H22a. I took mine off my H23A and replaced the one on my new H22A and it worked just fine. I have not had any issues with my ERG system after the swap.

Get your hands on the Helms manual and it should have the electrical information to test the device directly at its 3-pin harness for valid voltages, resistance, etc. If you do not have a helms and need the info, PM me and ill look it up for you.

Good luck-

brad

mr. r00t · 03-28-2005, 01:28 PM

Thanks man, I'll PM you for the specifics. What you're describing is what the mechanic did for me, took the EGR valve off the H23 and put it on the H22. He said he checked the voltages and D19 was discharging when it shouldn't be, which is why ECU sounds like it could be a valid problem.

xiaogou · 03-30-2005, 08:03 AM

On my Jdm H22 I have the egr as well. Can this system just be removed? Preferably without the CEL being tripped? I have been researching this, and read that some there is some wiring that can be done to bypass the CEL.

aneurysm · 03-30-2005, 08:08 AM

Quote:

Originally Posted by xiaogou

On my Jdm H22 I have the egr as well. Can this system just be removed? Preferably without the CEL being tripped? I have been researching this, and read that some there is some wiring that can be done to bypass the CEL.

As already said by someone else....it is not recommended that you bypass the EGR system- esp since you probably won't pass emissions, it also makes the car burn more fuel, etc, etc.

brad

[SUB[EX] · 04-02-2005, 08:40 PM

I have never seen a h22a with no egr. Even at the Hmotors warehouse. I looked at all the engines and picked the one i wanted.

If you remove the EGR you will always throw a code. I tried it. There are ways around it which i dont really remember. Mine was throwing it at one time also with the jdm ecu. And not with the usdm f22 ecu.
With mine i just needed to run the engine for a few days and the code finally dissappeared. I think the jdm ecu may be a little more sensitive to a bad egr.

As for your case, you can try a new ecu. but i would just drive it and reset the code every once in a while for a few weeks and see if it goes away.

xiaogou · 04-03-2005, 01:43 PM

I confirmed that engines in Japan do not have an egr system. An egr system has to be added before it can be shipped to the U.S. So, this also means that they would have to program the ecu to accept the egr system. Is there a way to unprogram the ecu? I have no emissions in Ohio, and am not worried about more gas consumption.

[SUB[EX] · 04-06-2005, 06:40 PM

Are you sure about that? I thought Japan Has way higher smog restrictions than here in the US. Isnt that why we get these engines by the boat load.

I dont think the egr had been added to either of my engines.
#1 there is no sign of a block off plate.
#2 the engines are technically not smog legal anyway so why would they go thru the trouble
#3 The jdm wiring harness is wired for the EGR.
#4 The Vaccum line to the Egr were present on every JDM motor i have seen, and with factory mounts
#5 Engines and ECU's are seperate usually in shipping. Why would they modify an ECU that is technically not mated to an engine.

As for removing the EGR. All you really need to do is wire something up that fakes the signal. Im sure a search will turn up what voltage is required.

The Block off plate seems to do the job for most of us.

PreludeRacer023 · 04-11-2005, 03:14 PM

im not sure whats going on here, JDM vtec have egr first off, my good friend put an h22 in his civic and used my car to corectly set up his egr....if u wanna get around it easily just get a p72 ecu, chipped or p28 chipped with a gsr program works better and makes more power, and it doesnt run lean .....mine ran 13.0 AF on the dynoall the way across...but the egr should work, i got no codes on my swap into an si with the jdm....something wrong with your setup

jsmooney · 04-11-2005, 07:56 PM

my above post was supposed to be sarcastic... Notice the drilling through the head to allow exhaust gasses to reach EGR... Hmm.. EGR is on intake manifold, not exhaust.... Guess when they brought them into the US they drilled it.. Along with the fact everyone of them has a EGR on it... And is wired up as said b4....Block it off and the code will go away... Other than that, best of luck...

mdpc20653 · 04-11-2005, 08:41 PM

get a p28 and chip it and set it up so it runs the IAB's (have dyno/tuning guy do it). with uberdata to start out with then you can do what you want to a degree.

mdpc20653 · 04-11-2005, 08:43 PM

then you can remap it or put an h22 map in it.

savesthedayrock · 04-12-2005, 01:04 PM

when i had my swap done the guy who did it, who is very knowledgeable with anything honda, said he used a p13 civic ecu and took out the egr cause it doesnt control it. my check engine light has never come on and i have been problem free...knock on wood...