my friend has a 99 civic ex and i'm helping him swap a 98 usdm h22a4. i was wondering if the prelude ecu will plug into his civic and run.

 

bump

 

I don't think it will work for two reasons:

1. I know the 99 Civic has OBD2B plugs, and I think the 98 Prelude has the different OBD2A plug-type ECU.

Check the ECU and see if it will even plug in, if it does that brings me to my second point, which I am sure of:

1998 Prelude has an immobilizer ECU that requires a chipped key, and the corresponding ignition switch.

 

i will work if u have a custom jumper harness..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1sickEJ &raquo;</TD></TR><TR><TD CLASS="quote">i will work if u have a custom jumper harness..</TD></TR></TABLE>

Yes it would plug in, but what would he do about the immobilizer? Can't start the engine without figuring out how to bypass the immobilizer...

 

Just get a p28 chip for your set up

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Nbboy7 &raquo;</TD></TR><TR><TD CLASS="quote">Just get a p28 chip for your set up</TD></TR></TABLE>

Few potential issues with that:

1. If he has to pass an emissions test to get a tag each year he'd be royally screwed

2. A P28 won't have EGR (not a big deal), but worse it won't have IAB/secondary butterfly controls to properly run the H22A with its stock manifold. now if he goes with an aftermarket or Euro R IM that does away with the IABs then this isn;t an issue either.

I mean sure he can go jumper harness with an OBD1 ECU of his choice, but emissions usually hampers most people from doing that.

 

Run a chipped P72 or modified chipped P28 for the IAB. Then put the stock ex civic ecu in before the emissions test and you should be fine.