Doing a 2.3l Turbo swap from a 88 t-bird to an 89 mustang notch, I have heard that it's easy to just repin the computer from a thunderbird and reuse the mustang engine harness. But is there anything preventing me from just swapping the engine harness from the thunderbird (it seems to me to be by far the easiest? I have no parts car, but I do have the engine harness/ecu (La2). Thanks
I always repin its much easier. I dont think you want to remove the wiring harness. I would NOT. Most of the pin out is identical except the preamium fuel switch and VAM sensor. You can even leave the MAP with the vacuum hose disconnected for your turbo swap. Their is not that much to repin in that conversion.
Tom Renzo is telling you correct the 88 harness is a mess of wiring. I pulled one for spare connectors just in case. It has the brakes wiring and other mess in it. Maurice
Alright, time for me to show some of my ignorance (wiring is the one part of vehicles I blank out on).I have the engine in the mustang (seal and shined).
My idea of a wiring job is splice and butt connectors. Plan on getting a soldering unit.
I've read and noticed that cutting and splicing into pin 46 willy nilly isn't such a great idea. Anyone have any advice on what to do concerning this, (pics would be great, i'm electrically retarded)?
46 is the signal return wire. You have to splice into it. The best way is cut the wire. Slide some heatshrink onto one of the wires. Now spice in the vam wire. [Can't remember which] Solder it and wire you cut. In other words only reason you cut the wire is to get the heatshrink on the wire. The 2 wires go back together with the vam wire. And then use the heatshrink to seal it. Don't use butt crimps. They are just a nightmare later when the copper corroded in them.
The wiring isn't that bad. Just do a nice neat job. Just double check everything. Me personnelly I removed the vam harness from the turbocoupe one and repinned at computer then spiced in the one wire. But I done this when I didn't have the website info. I took the 89 harnesss and compared it to a 86 harness and figured what wires needed moving. need more help ask. Maurice
I was looking at this wiring diagram http://www.flemworld.com/diy/Images/MTCWD.jpg and can see an awful lot of Ts into the pin 46 wire. Splicing the Vam wire into it won't interfere with anything? Thanks for all the help
These are Flemworld's wiring instructions. I used these when I swapped the turbo motor and LA3 into my '89 convertible. Followed them to the letter and they worked great!
Turbo Swap Wiring Instructions 88-90 Mustang: Note: You will see pin wire 46 mentioned throughout the steps below. This pin wire should never be removed or cut out. When instructed to T-in or splice into this wire simple connect the new wire to this existing wire using a piggy-back connector or similar connection. Several sensor share this wire to send signals back to the computer. The computer knows which sensor is sending the signal by the signal the sensor sends. Cutting the wire out will result in some sensors not being able to report back to the computer. Map Sensor = The Turbo Coupe motor uses a BAP sensor (Barometric Absolute Pressure) to make corrections to the fuel and timing tables based on different altitudes, the Mustang uses a MAP sensor (Manifold Absolute Pressure) to perform this same function. The MAP sensor will work with the Turbo Coupe motor by simply unhooking the vacuum line that runs from the sensor to the manifold or vacuum tree. Thus allowing the MAP sensor to read outside barometric pressure instead of manifold pressure. Do not plug the MAP sensor vacuum port on the MAP sensor itself, only the manifold or vacuum tree port. Leaving the MAP sensor vacuum port open allows the sensor to read the outside barometric pressure instead of the manifold pressure it would normally if connected to the vacuum source on the manifold. VAM Meter = The Turbo Coupe motor uses a Vane Air Meter (VAM) to calculate the amount of air entering the motor. The stock Mustang motor does not have VAM Meter. You will be using three of the wires that used to go to the EGR position sensor to connect the VAM. Click here for a diagram of the VAM Meter connections. · Locate the EGR position sensor plug (3 Wires - Orange/White, Black/White, Brown/Lt-Green) on the Mustang EEC engine bay harness. · Cut the Orange w/White stripe wire (Pin Wire 26) from the EGR position plug and connect it to the VRef (Orange w/White stripe) wire from the VAM harness. · Cut the Brown w/Light Green stripe wire (Pin Wire 27) from the EGR position plug and connect it to the VAF (White w/Black Stripe) wire from the VAM harness. · Cut the Black w/White stripe wire (Pin Wire 46) from the EGR position plug and connect it to the VAM Signal Return (Black w/White stripe) wire from the VAM harness. · Move the Dark Green wire (Pin Wire 33) from the EGR Vent Solenoid on the Mustang Computer plug to pin 43. · Locate the EGR vent solenoid plug (2 Wires - Red and Dark Green) in the engine bay and cut them from the EGR Vent sensor plug. Connect the Dark Green wire (Now Pin Wire 43) to the Vane Air Temp (Light Green/Purple) wire. Cap off remaining red wire to EGR Vent Solenoid. EGR Control Valve= Although all of the other Turbo conversion web sites for Mustangs state to disable or remove the EGR. I suggest re-pinning the wires on the EEC, using the stock Turbo Coupe EGR valve and hooking up the EGR as it was on the Turbo Coupe motor originally. The Turbo Coupe EGR sensor only needs one sensor hooked up (EGR Control) as opposed to the Mustang EGR system which uses three sensors (EGR Vent, EGR Control, EGR Position). You will basically be dumping two of the sensors (EGR Vent , EGR Position) which the Turbo Coupe computer does not have provisions for anyway. Click here for a diagram of the EGR Control Solenoid connection. This step can be omitted if you wish not to use the EGR control solenoid. · Move EGR Control Solenoid (Pin Wire 52) Yellow wire to pin 33 on the Mustang computer harness plug. Premium Fuel Switch = The Turbo Coupe computer has a provision for a premium fuel switch which allows the driver to use different timing and fuel curves depending on the octane rating of the fuel being used. Most will say to just wire this so that it is always in premium mode but I like the advantage of being able to run lower octane fuel if I choose. Click here for a diagram on wiring in a premium fuel switch. · Mount a toggle switch or equivalent switch some where on or in the dash or console. · Locate the Green w/Purple stripe wire (Pin Wire 24) at the computer. This is the AC idle adjustment wire which is triggered off the AC system. Cut the wire from the computer plug about 5 inches up. Cap end of the wire left in the harness as to not short anything. The signal for this wires comes from the AC not the computer. · Connect a new wire onto the 5" wire at the computer harness plug and run it to one side of the switch you installed. · Run a new wire from the other side of the toggle switch and connect it to (Pin Wire 46) Black w/White stripe on the Mustang computer harness. Note: Do not cut pin wire 46, simply T-in or splice in the new wire. Note: If you wish to connect the Premium fuel switch so that it is always set "On" simply run connect the end of the 5" wire to Pin Wire 46. Make sure you t-in or splice into pin wire 46, do not cut or remove pin wire 46. Optional Stock Electronic Boost Controller = The Turbo Coupe computer is equipped with a electronic boost controller valve. It is recommended that you upgrade to a manual boost value for higher boost pressure but if you wish to retain the stock electronic boost controller valve follow the below instructions. · Run the Pink w/Black stripe wire from the boost controller valve to Pin wire 31. · Splice in the Red wire from the boost controller valve to pin wires 37 and/or 57. This is the Red wire that was capped off when hooking up the VAM meter which was from the EGR vent solenoid. Do not remove pin wire 37 or 57. T-in or splice in to the existing connection.
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'89 LX ragtop with turbo'd TC motor - Thunderstang!
'86 Turbo Coupe (daily driver)
'88 Turbo Coupe (parts car)
Mustang 2.3T swap 
