claytski

have a 91 80q and have a mc2 swap going. the mechanical end is easy. I have the red harness from the 200t(mc2) and the fuse/relay tray, and the ecu. do I just pull the old harness out and put the new one in? I did notice that the little red wire for the starter isn't in the mc2 red harness. also, is there anything I need to slice in? if you could give me some direction, that would be great. thanks.

do I have to take out the dash to get the wires to the ecu by the glove box?

Jim Bush

it is only for the motor stuff mainly.

A good site for explaining things is:http://4ktq.digitalnoise.org/4/index.htm
It is for a 4000 but it is close.

If you have any specific questions, just ask.
I am just done with the same thing.


Jim Bush
Holland, MI<ul><li><a href="http://4ktq.digitalnoise.org/4/index.htm">http://4ktq.digitalnoise.org/4/index.htm</a</li></ul>

Jim Bush

So it may not be as helpful but it is close.

Jim Bush
Holland, MI

claytski

ok, let me narrow my questions. first I am unsure of exactly what year this is out of. I have a bently but I know there are slight variations between years.

my main questions are these:

there is a large red connector and a large white connector on the inside side of the harness. it also has the ecu connector and vacuum line. it also has a few smaller ones. my question is where do these go. where do I plug them in inside the car.

next: where do I mount the ecu?

next: included is another fuse/relay tray. do I just unplug everything from the back of my old one and plug in the one from the mc2?

thanks.

Jim Bush

A MC2 uses a MAC-14 ECU (two knock sensors) the MC1 uses a MAC-11 (one knock sensor).

I didn't use the white connector. The red connector; I spliced several wires from there into the cars harness under the instrument cluster, you should have the ISV controller also (it is a double relay), also I hooked the switched power under the cluster.

I mounted the ECU under the climate control behind aux. gauges, your 80 probably has a big shelf right there but there may be enough room behind it?

Jim Bush
Holland, MI

claytski

ok, what does that white connector do that you didn't use? I do have the ISV controller. what wires do I need to splice from that red connector to my harness?

Jim Bush

These are for the MC1 harness yours may be different, also use at your own risk, mine is running this way.

Pin 7 from ECU (V/BK) goes to the tach
Pin 14 from ECU (G/V) goes to BL/Y wire from MTFS at Yellow connector on back of cluster
Pin 21 from ECU (BR/G) goes to pin 47 under fuse panel (Fuel pump relay)

I have one more and don't remember what that one was for, the red harness had a BR/Y wire that I spliced in and ran to a G/V wire???

The white connector was for the economy computer if I remember right.

snowman0650 at gmail.com if you need something further,

Jim Bush
Holland, MI

devil's advocate

wow it sure is an improvement. The white connector, if i recal has 6 or 8 very small gauge wires, went to the trip computer on the 200. I did not use it either.

devil's advocate

I took the pain to trace all the wires with the diagrams and pin outs as i disected the donor car to make install as painless as possible. I think it came down to connecting a few wires in the car, most from the red connector.

thick black wire - ignition hot
2 blue wires with black tracers - ignition hot
red, black tracer - 12V constant
purple/ black tracer - tach signal (i used terminal 17 of the ignition controller bhind passenger side kick panel)
brown - ground (there are`a few)

I think i had to connect a few wires within the harness to maintain the connectors for vag-com hook-up. only thing under the hood was wiring for the warm-up regulator, which i spliced in to the O2 sensor heater.

HTH

lemieux@curbside

DAMN !! never saw that site ..thanks !!