Installation Notes: MSD 2-Step on your 2018-up Mustang GT
⚠️ WARNING ⚠️
The MSD 2-step box is not intended for use on Direct Injection 2018-up Mustangs. This serves as only a guide and Lethal Performance is in no way responsible for any issues that arise from completing this installation.
NOTE: This serves as a supplement to the complete MSD instructions and is not a complete installation guide. Click here for the full MSD instructions.
Plugging the MSD harness into the engine harness at the coils:
Where your factory engine harness plugs into the MSD harness there are 2 wires to the connector: a purple wire + another color (varies). You will want to ensure that the purple wire on the engine harness side always mates to the gray wire on the MSD harness connector. These are your power wires so failure to meet them will result in malfunction.
NOTE: You may need to shave off a nipple inside of the connector for a solid, smooth connection as the product is set up for 2015-2017 cars.
Cylinder #6 may have (2) purple wires. You will use cylinder #5 as a reference on the location of the correct purple wire to mate with the gray wire (ex: if the purple wire on cylinder #5 is on the left, then use the purple wire on the left of cylinder #6 to mate with the gray wire on the MSD.
Plugging the MSD harness into the engine coils themselves:
This part is fairly straightforward except for cylinder #3, which has a remote coil due to the Direct Injection mount.
For cylinder #3, you will need to reverse the polarity of the wires at the coil side. You will need to pop off the blue cap and using a small pick or flathead pop the wires out of the connector.
You will reverse them and place them back into the connector (in most cases you will be putting the gray wire on the right side).
NOTE: You may need to shave off a nipple inside of the connectors for a solid, smooth connection as the product is set up for 2015-2017 cars.
Plugging the connectors on the MSD box:
Like the standard 2015-2017 Mustang install, you will want to make sure that the connector with the group of gray wires (your power wires) is connected to the single red wire connector (red=power). Next, the connector with the group of black wires (your trigger wires) will plug into the connector with the tan wires. The last connector is your activation wires and will plug into the ground & activation wire harness.
NOTE: This serves as a supplement to the complete MSD instructions and is not a complete installation guide. Click here for the full MSD instructions.
If you have any questions, please reach out to our tech representatives by phone at 561-753-8105 or email support@lethalperformance.com .