This is an instruction guide to assemble your coil on plug setup for a Mitsubishi Evolution 4-9. This is a step by step guide for your personal use. JD Customs USA is not responsible for any accidental damages that may occur during the assembly or use of this kit.

You can purchase your JDC DIY Coil-on-Plug kit HERE

Tools needed:

  • Crimping tool (needle nose will work)
  • Wire Cutters 
  • Wire stripper/ hobby knife
  • Measuring tape or ruler
  • Patience
  1. Cut three of the following wire lengths: (3) 5” & (3) 16.25”. You should have a total of 6 wires when finished. Group this set together.
  1. Cut one more set (3 wires each) of 14” & 18”. Group this set together. Do not mix the two wire sets together.

  2. Strip 1/4” from one end and 1/2” from the other for each wire. Be careful to not mix up the two different groups of wires.

  3. Twist the 1/2” end of the 5” & 16.25” wires together and repeat two more times until all 5” & 16.25” wires are joined at one end as seen below.

  1. Repeat step number 4 for the 14” & 18” wires.
  1. Crimp a pin for the Evo male connector to the end of each joined wire. The pin will need to be crimped so that no edges are sticking out, which will keep it from fully snapping into place inside the connector. Make sure to make a tight connection and pull on the pin before inserting it into the connector. Your wires should look something like this:



  1.  Slide one insulator on the set of two wires coming out of the Evo connector to insulate the male connectors before inserting an insulator on each single wire to insulate the Denso connector. Do this before attaching the Denso pins to the ends.



  1. Crimp Denso pins to the end of each single wire. There should be 12 total including both sets of wires. Do not plug them into the connectors yet.



9. Individually insert the three joined 5” and 16.25” wires with pin into a single Evo male connector. Repeat with the 14” & 18” wires on the other Evo connector. Make sure the pin is crimped in a way that allows it to insert into the connector without resistance or it will not snap into place. Sometimes this takes a few tries since you are putting two wires into one connector. You should hear a slight click when the pins snap into place. You can also look into the front of the connector to make sure the tab is pressed in and holding the pin in place. Give the wires a good tug to make sure they are secure before moving onto the next step. The pins should be the same length when looking into the end of the connector. If one is shorter than the others, you do not have it snapped in, and it will result in a misfire.

This pin is not secured by the locking tab.

This pin is secured. Notice the difference in the height of the locking tab.

You can use a small flat head screw driver to push the rubber insulators into the connector. Your harness should now look similar to this:


  1. Group the shorter and longer wires together coming from the Evo male connector and pull them to one side of the connector to separate them from each other.

  2. Cut just enough wire sheath to cover the wire groups.
  1. Starting with the set of shorter wires, insert the “+12V” wire into the proper length wire sheath and connect it to the Denso connector “+12V” port (see connector guide below).


  1. Insert the “Ground” wire into the wire sheath and connect it to the Denso connector “Ground” port.
  1. Insert the “Pulse” wire into the wire sheath and connect it to the Denso connector “Pulse” port.
  1. Follow steps 11-14 with the other connectors to complete your wire harness. You can use a 1-2” piece of wire and another Denso pin with insulator to make a plug for the unused port in the Denso connector. This will keep water from getting inside the open port.

                               Your finished harness should now look similar to this:

  1. Clean the top of each coil with rubbing alcohol and a paper towel and let it dry before attaching the JDC logo. Simply peel the clear transfer tape from the sticker and apply the logo to the center of the coil. Press firmly or rub with your fingernail until all the bubbles are gone. Carefully pull the transfer tape off and make sure all parts of the logo stick correctly. (Newer kits come with different stickers that are easier to apply)

  1. Mount your coil packs to the mounting plate with the provided mounting hardware and connect the harness to the coils according to the wiring diagram under step # 1. The provided washers should go between the coil packs and mounting plate in order to make the coils mount flush to the plate.
  1. Mount your Coil on Plug setup to the valve cover using the two provided hex head bolts and washers and plug in the harness to both Evo connectors.
  1. IMPORTANT! Make sure you swap the provided 15A fuse in the fuse box on the driver side under the dash. The cop ignition puts out more power than the factory 10A fuse can handle and it will eventually blow and your car will not start if it does. It is located near the driver seat by your left knee in the interior fuse box, top left, red fuse, #1 position. 

  2. For Evo 4/5/6, refer to the picture below to find your ignition fuse:
  1. Enjoy your home-made COP kit from JD Customs USA!!

Don’t forget to upload a picture and tag us! We love to see our products go to work! Also make sure to tell your friends where to purchase their Evo DIY COP kit! We appreciate your business!


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