IAT/ECT Installation - Version 2 (Pots Mod)

IAT/ECT Installation - Version 2

Submitted by Aaron Taulbee (Setzer715)

Note: You must be able to solder for this Mod.

Parts needed:

  • A Double Pole Single Throw (DPST) switch
  • A 20’ role of 18gauge red wire and black wire
  • A splice connectors (Red ones) that look like long skinny barrels or cylinders.
  • Tie straps and Electrical tape
  • 2 Trimmer POTS, the types to buy are completely up to the individual. You can buy linear ones so you know exactly the amount of resistance your applying. You can also buy ones that are mountable so you can mount them somewhere in the car for easy adjustments (recommended). I bought two very small and very cheap ones and put them inside a small kit box. The box way works, but no it is very difficult to tune them, I have to take my car apart to do it. The choice is up to you.

Tools needed:

  • Soldering iron and associated equipment
  • Phillips screwdriver. More screwdrivers/tools may be needed depending on where you will be mounting the switch and the POTS.
  • Wire cutters, wire strippers, and crimpers.
  • Drill for mounting the switch

First off you have to build the circuit.

  1. Take everything out that you bought at Radio Shack/Electronics Store and start to heat up your soldering iron.
  2. Take your black and red wire and cut it into 4 5’ sections of each color.
  3. Using tie straps or Electrical tape, strap one black wire to one red wire. Do this for all 4 wires.
  4. Next you have to solder. We’ll start with the POTS first. Note: If you want, you can use some heat shrink on each connection to ensure they don’t touch. Note2: If you plan on using small pots and a kit box, then the set of wires going from the pot to the switch can be significantly shortened since they will be inside the box. Take one set of wires that you strapped together strip and tin the ends. Take another set and strip and tin those ends. Take the two red wires and solder them both to the center pin of the pot. Now solder the two black wires to one of the outside pins. Doesn’t matter which one, the difference will be which way you have to turn the pots to turn them up and down. Just try to get both pots the same; you can use a multi-meter to accomplish this. Now do the same thing for the other POT.
  5. Take one set of tire strapped wires from one pot and strip and tin those. Do this for the other pot as well. Now solder one set of tinned wires to each pin of one side of the switch. It doesn’t matter which wire goes which pin. Now take the set of tinned wires from the other pot and do the same on the other side of the switch.
  6. Use a little electrical tape or heat shrink to cover all exposed pins. If your using small trimmer pots and bought a kit box, now would be the time to cut a slit in the box and put the pots inside of it. Soldering is complete and you’re ready to install in the car.
  7. Take your center dash apart using the Phillips screwdriver. There will be two screws on the part that covers you parking break towards the rear on the sides. After removing that, there will be two screws just behind the shifter where the front of the last piece you took of was. Lastly remove the 4 plastic tabs up in front of the cup holders. Unscrew your shift knob and the whole piece should come out.
  8. With the center counsel removed your computer and wiring harness is exposed. Find the Blue wire with a white stripe/Pin #38 on the harness. Get a good spot to cut the wire and cut it. Make sure you leave enough room on the end going to the harness to be able to strip the wire and crimp to it. Now strip both sides of the wire you just cut. Take one set of your POTS wires and strip those. Using your crimpers, crimp one of your splice connectors to each of the wires you just cut. Now crimp the wire that is going to the computer, it’s the one going into the wiring harness, to the Red wire of your pots mod. Crimp the wire going to the sensor to the Black wire. Next, find the White wire with a green stripe/Pin #39 on the harness. Repeat previous steps for this wire as you did the Blue and white wire.
  9. Now find a location to mount your switch and POTS. Drill the required holes and mount them.
  10. Put your car back together and go and try them out! Note: If you decided to have the POTS hidden behind the dash in a kit box, I recommend adjusting them to your liking before putting your center counsel back together.