If you have a 88 FC Turbo II engine harness but have an FC 89 Turbo II engine, would the harness still work? Would you need to cut or change anything for it to work? Also the same goes for the ecu.

 

Fundamentally it will work. But to make things a LOT easier, you should swap the S4 electronics (TPS, injectors, pressure sensor) onto the S5 engine. This assumes no emissions. You'll need to swap the S4 front cover to run the mechanical metering oil pump, or go to premix.

 

I don't really have all the other swap, I'm just buying a 88 turbo II shell and I have an s5 engine ready for swap. Would it be skater to just get a newer harness?

 

I would just find a S5 harness for ease of installation if nothing else.

 

You can't just get an S5 emissions (EM) harness & expect to have it plug right into an S4 car. There are significant differences between S4 and S5 wiring/sensors/ECUs. The EM harness plugs into the front (F) harness, which connects to half of the car. Plug shapes are different, wires are in different locations, etc... You would also have to get a hold of an S5 TII AFM & boost/MAP sensor if you don't already have them. All sensors must match the ECU.

The route Aaron suggested is much easier than the alternatives. You'll either end up having to track down virtually ALL of the S5 harnesses to swap into the car, or you'll end up cutting and splicing lots of wires.

 

I have an 89 convertible with turbo II motor running, and i want to swap it over to the turbo II shell. The harness is kinda messed up so i just wanted to know if i an 88 harness would work since i'm new to all of this.

 

Short answer: no. If you were not the one that did the turbo conversion on the '89 convertible, I'd be willing to bet it has an S5 NA emissions harness. Get another one and modify it as explained in the link in my sig. It will be easier than an S5 TII EM harness, and leagues better than hacking up/splicing an S4 TII EM harness.

To take all of the harnesses/sensors/ECU/engine/drivetrain out of your '89 convertible and put it in an S4 TII is a LOT of work, but if you're up for it, go ahead. My advice would be to start studying the S4 and S5 wiring diagrams before you start. There are many differences you'll have to account for. You can get both here: http://foxed.ca/foxed/index.php?page...nual#secondgen

 

Cool, thanks. I'll look into it more.