Engine Wiring Harness Question...Swap a Mk3 Harness for a B4?

G60ING

Top Post Dawg
Joined
Aug 5, 2001
Location
MD
TDI
No TDIs Currently, I have an R36 Corrado. I've had an ALH Corrado swap, AHU Corrado swap and 2003 TDI Jetta
I'm doing a TDI swap into a corrado using a Mk3 as a donor. But the wiring harness of the Passat fits the holes on the corrado's firewall a little better then the Mk3 harness. I spent a couple hours last night comparing the wiring diagrams for both bentley manuals and at first glance it looks like there should not be any problems with using a B4 1Z harness on a 1998 AHU Mk3.

Does this sound reasonable or am I the only oddball to venture down this road?
Thanks:)
 

Lug_Nut

TDIClub Enthusiast, Pre-Forum Veteran Member
Joined
Jun 20, 1998
Location
Sterling, Massachusetts. USA
TDI
idi: 1988 Bolens DGT1700H, the other oil burner: 1967 Saab Sonett II two stroke
Whose ECU will you use? The B4's, or the A3's?
The 1996 B4 harness has provisions for the temp sensors at the cat and the pump wiring for the supplemental 5th injector.
These components were deleted from the 1997 model year so a 97 B4 harness should be compatible with the A3 ECU.

The sensors and their feedback through a 96 B4 harness to a 96 B4 ECU can be mimiced easily enough if the equipment isn't present, but it's one step to consider.

A 96 B4harness with the 97 B4 ECU, or an A3 ECU may be problematic if the harnesses are differently wired at the ECU because of these component deletions. It's uncharted territory to me.
 

G60ING

Top Post Dawg
Joined
Aug 5, 2001
Location
MD
TDI
No TDIs Currently, I have an R36 Corrado. I've had an ALH Corrado swap, AHU Corrado swap and 2003 TDI Jetta
Does anybody know what pins on the ECU plug these emission parts are?
 
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