A Little Blog

Taking a chunk of wire out of the harness did improve matters for me, but not quite enough and more needs to come out. This time, however, it’s extra plugs that are being removed.

One of the recommendations on the forums was to create an adapter harness to go between the A4 and A6 plug mapping so you don’t have to cut up the 2.7T harness. This seems good in theory, until you realize you need to cut into the harness upstream of the A6 plugs anyway.  The adapter harness really just ends up being a bunch of extra plastic bulk that won’t fit into the plenum chamber (and you need to make sure that’s closed so the ECU and/or your feet don’t get wet).

Started with the slow process of cutting individual wires on either side of the A6 plugs and immediately reconnecting them. Doing it one at a time made it easier to organize the wires by plug. By grouping the wires together I hope to better bundle them to save space.

A short 6 hours later the majority of the extra plugs are removed and the wire rearranged. I can now fit the TCU and ECU both into the plenum box. there is, however, still a long way to go to tame the rat’s nest enough that it will fit back into the plenum box.

Turns out an extra long wiring harness makes it a little hard to close the hood, so after getting some confidence the wiring was reasonably good I took about 4 feet out and added in some connectors so the transmission and engine harnesses weren’t permanently connected.

Hood closes now. Now I just need to figure out how to get the dash computer to play nice with the older transmission control unit. Progress.

There doesn’t seem to be a matching part in the donor A6 and I can’t figure out where in the harness I would plug in the booster. So… it’s coming out.

Not only does it fire up, but it moves under its own power. Unfortunately it’s stuck in 2nd or 3rd gear until I get the A6 TCU to play nice with the A4.