BELLOW DOESNT BELONG TO ME I FOUND IT AND THOUGHT IT MIGHT HELP YOU A BIT : THIS GUY HELPED ME OUT BIG TIME
Here I've gathered up all legitimate EK wiring information on frequent wiring issues people have when performing an OBD2 B-series
engine swap into 96-00 EK civics:
96-98/OBD2a CIVIC CX/DX/LX/EX WIRING INFO
1) If reusing a CX/DX/LX engine wire harness you will have to perform these wiring mods to this harness:
a) add wiring for the VTEC Solenoid (VTS) & VTEC Pressure Switch (VTPS)
b) perform the IACV mod
c) add wiring for the Knock Sensor (KS) - IF - using an OBD2 DOHC VTEC ecu or non-reprogrammed OBD1 DOHC VTEC ecu
d) possibly extend the 2nd 02 wiring (if you're using a US OBD2 B-series ecu)
e) perform the OBD2a CKF mod - click HERE
Before, I mentioned to swap the CKF plug over to an integra CKF plug, but this wiring trick is much easier to do.
2) 96-98 Civic users can use a 5-speed
96-98 EX engine harness to complete their engine swap if they do not want to perform the mods listed in #1, with exception to #D & #E. The 5spd* EX harness has all of the A-C mods integrated from the factory. The only downsides is that you will have to wire in the 2nd 02 sensor manually if using a US OBD2 DOHC VTEC ecu. Using a 5spd EX harness is virtually plug n' play with the exception to extend a few wires and perform the CKF mod (#E).
*Using a 5spd EX harnesses will greatly cut back on performing most of the wiring mods listed. Make sure you get a 5spd EX harness and not an AUTO EX harness! The EX AUTO harness is designed differently than the 5spd EX harness; you will run into obscure issues with an auto EX harness, that I have yet to figure out.
NOTE: You
CANNOT use an OBD2 integra engine wire harness in any 96-00 civic because of its 2-piece design. EK civics all use a 1-piece design engine wire harness making it impossible to use an integra engine wire harness in an EK chassis.
3) OBD2a wiring information/diagrams can be found on my technet site here, under the wiring section:
.:FFS TechNet:.
4) If you plan to use a 99-00 Civic or 00-01 integra ecu into a 96-98 EK civic, you will
NEED a OBD2a->OBD2b jumper harness adaptor. Reaonsbeing is that OBD2a & OBD2b ecu plugs differ and are incompatible with each other. A handful of people sell this type of ecu jumper here, including me.
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99-00/OBD2b CIVIC CX/DX/LX/EX WIRING INFO
1) Same wiring info as OBD2a in regards to using a CX/DX/LX/EX engine wire harness, but respective to
OBD2b ecu pin out locations.
1b) Honda changed to a smaller distributor(dizzy) plug on all 99-00 EK Civics (CX/DX/LX/EX/ except Si model. This smaller dizzy plug is
incompatible with OBD2 B-series distributors. You will have to either change change over to an Si dizzy plug, 96-98 civic dizzy plug, or 96-01 Integra dizzy plug in order to be compatible with a OBD2a/b B-series distributor.
Some images to help understand...
96-98 civic / 96-01 integra dizzy 'big' style dizzy plug:
99-00 civic small style dizzy plug:
2) OBD2b EK non-VTEC civic owners have an optional choice of using a 99-00 Si or EX engine harnesses (5spd). Again, there is no need for you to add VTEC wiring or perform the IACV fix because like a 96-98 EX harness, its already pre-done from the factory on the OBD2b Si / EX harnesses. The CKF info remains the same for the EX harness. The differences between an OBD2b Si and EX harness is the distributor plug and CKF plug - Si uses a B-series dizzy & CKF plug.
One issue that might arise is the 2nd 02 sensor if using an Si coupe engine harness. You will have to manually wire in the 2nd 02 because the Si engine harness only has the primary 02 sensor integrated into it. The 2nd 02 is part of the cabin harness on Si coupes & I think 99-00 EX coupe's as well (correct me if I'm wrong).
3) If you want to use a US 00-01 integra ecu in your 99-00 civic, you need to have the Immobilizer removed from the integra ecu or else your civic will not start. Also, when using a US 00-01 Integra ecu w/removed IMMobilzer, the fuel pump pinout "A16" needs to be moved to over on slot to "A15", in order for your EK to start (fuel pump pin location differs between OBD2b civic & integras). You only need to perform this pin change if using an 00-01 US integra ecu's in a 99-00 civic. If you plan to use an Si coupe ECU, there is NO NEED to perform this pin swap because Si coupe ecu's do not have an IMMobilizer, nor does any 99-00 civic ecu, only 00-01 integra ecu's do. Don't forget that if you ever switch back from using a US 00-01 integra ecu to an Si coupe ecu, switch the A15 pin back to A16!!!
4) 3) OBD2b wiring information/diagrams can be found on my technet site here, under the wiring section:
.:FFS TechNet:.
Code 91 Issues - pertains to both OBD2a & OBD2b vehicles
There's a MIL code (91) that some of you might get. This is for the fuel tank pressure sensor or "PTANK" as honda labels it. This happens when using a US OBD2 integra ecu in an EK civic, but it's also chassis specific related - as in some civics have this PTANK sensor while other's don't. There are a few fixes for this annoying code and you can read my article about it here:
.:FFS TechNet : OBD2 Code 91 Issue & Fix :.