https://honda-tech.com/forums/showth...2974744&page=6

Above is the link to my build that I have going on. I am using a 99 chassis with a 98 engine harness with no issues. However the issue or question that I have is the car was an auto until I did this swap and the auto ecu used four plugs where as now I am only needing three. All three that are needed are plugged into the conversion harness and hooked to the ecu along with the green plug. Is the extra plug left over needed?


I know that it controls aspects of the auto transmission but I just wanted to know if any wires on it are needed for the swap? I have the haynes manual out as well as three other auto/manual swpa write ups but they are not talking about this plug. I was able to find a write up from 4 years ago with another person asking this same question and I asked if he ever got an answer but he never responded back. Any help would be appreciated. Thanks

 

The 96-98 Engine harness that plugs into the ECU is different from the 99-00 engine harness as part of that (99-00) harness is part of the cabin loom (your extra plug above). You'll need a 99-00 harness or try and rewire that plug to the other 98 plugs you have (good luck).

 

Just to make sure I am tracking. The car is a 99 civic d16y8 auto that I have converted to a 98 d16y8 manual. I swap the engine with the 98 engine harness. The same harness was on the engine in the 98 car. I am using the 96-98 conversion harness for 0BD1.

 

It just clicked with what your saying. The extra plug that I have hanging controls the Fuel pump and relay where as the 96-98 harness has those wires in it. So I would need to go through and run jumpers from each of the corresponding wires or just try to repin it? What do you think?

 

I know that I cannot be the first person to try this so has anyone else done this and had to repin the plugs? If so can you chime in please.

 

Can anyone chime in with help here. I know that I cannot be a pioneer by being the first person ever to try to use a 98 engine harness in a 99-00 chassis. If there are wires that need to be repined or something I would love to know. I still have the 99-00 auto engine harness if that helps.

 

just use your auto harness way easier you can strip out all the extra plugs if you want to . there is a reason why nobody does obd2a harness in obd2b or the other way around

 

OK I have gone back through and swapped out the 96-98 manual harness with the 99-00 auto harness. Granted I have a few extra plugs left which I understand why since its for an auto. I have gone through and did the three wire to two wire IACV swap and moved the pin on the "B" plug. I still get no fuel pump prime and no fire? Any thoughts?

 

I'm trying to run everything through my head to make sure I didn't miss something. All fuses are good and if I jump the relay I can get it to click and the fuel pump to prime. All parts worked prior to beginning the swap.

 

Also do I need to do the fuel pump wire swap at the plug? I see that its for am Integra but at this point I am asking to make sure. As of right now I am dead in the water.

 

recheck all you grounds also .

 

Well we are finally up and running. A fuse was the issue, by the fuse not being in the socket at all! I cannot believe I missed that but it happens. The car is starting right up, however I am getting the up and down idle like many others have complained about. I'm trying to check all vacuum lines to make sure theyre good to go. Thank ya'll for your help