Ok, I'm going to be running a megasquirt to control my engine (88 T2 in an 88 'vert), and thus will be ditching the stock computer and emissions harness (and parts of the front harness: the CAS, alternator, and coils, among a few other small things, are in there on my car).

Does the ECU control any other functions of the car, such as operation of the top, headlights, or other random little functions? I dont think it does, after checking the FSM, but I just want to make sure.

Also, are signals from the front harness to the cabin or rear harness routed thru the emissions harness? Would I need to reestablish any connections between harnesses if I remove the emissions harness to run my own?

 

You'll need to fish out the wires for the wipers from the engine harness since they go through with the engine harness. I believe there's also something elsee that ties into the engine harness loom as well but its slippin' my brain right now...

 

oh, right, i forgot about that, since the wiper motor is right there. Theres also the cold-start pump thing (little tank of antifreeze up next to the charcoal canister... thats now sitting in my garage) And I thought that was the emissions harness (the one that goes thru the firewall high on the pass side under the wiper motor/charcoal canister), whereas the engine harness was the one that connected to the batt, CAS, coils, and fuse box. Just to try to avoid confusion...

 

Well to ultimately avoid confusion there is no emissions harness

The engine harness runs through the pass. (right) side
The body harness truns through the drivers (left) side.

Yes, some engine functions like the CAS are ran through the body harness, but that is the essential division, body on the left, engine on the right.

All of the emssions items such as the BAC and ACV won't require any wiring. Im unsure of whether or not the MS has an idle control feature such as the Haltech, but if it does and you want to use your BAC, you'll be using new wires from the EMS anyways. All the old stuff can be tossed.

 

ok, i just remember the FSM labelling that as the emissions harness, but i may have mixed it up. Im dropping basically everything that isnt essential to the car running, so that should simplify the engine bay a bit.