Gen 2 JMS FuelMax PowerMax install under rear seat.

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Today I installed a JMS fuel max in my 2019 Ford Raptor. It was pretty easy, only took about 2.5 hours and required no special tools or skills. The kit from MPT is plug and play for the ford raptor. The only exception was the ground wire eyelet was way too small for the available ground lug in this install location. I had a spade terminal available but would highly recommend a 1/4” ring terminal for permanent and better install. Scroll through pictures before reading instructions to visualize better. FYI, JMS includes and says to replace the under hood fuel pump fuse with a 30 amp fuse. I cannot say for sure for all gen 2 trucks but my 19 had a 30 amp installed already. Spot 50 on the fuse block.

FPDM = Fuel Pump Driver Module

Items needed;

1/4 ratchet and short extension
8mm socket
10mm deep socket
13mm socket
T25 bit
T50 bit
1/2” drill bit or small sharp exacto knife
Wire loom - optional
Wire crimpers
Wire stripper/cutter
Electrical tape
Ring terminal for ground
Quality creeper and led light




You can start with the FPDM harness or fuel pedal signal wire but I started from the rear and worked up.

I found it easier to park the truck on smooth and level surface and jack up the driver side of the truck to make more room while underneath the truck.



1. Lay down rear drivers side seat back, videos available if you’ve never done it. There’s a latch behind the seat and you have to finesse the mechanism.

2. Remove amp and sub box. 10mm and 13mm 1/4” socket and extension. Then pull back interior fiber/carpet stuff to expose metal. You’ll see an oval rubber grommet. You’ll bring the FPDM wire through here.


3. Loosen and remove 6 T50 bed bolts, lift and slide bed away and to the right of the cab. The fuel filler neck will prevent much movement but you only need about 3”.

4. Crawl under truck to FPDM, located above and between the rear of the gas tank and exhaust on the frame rail. Directly next to the rear brake lines bracket.

5. Disconnect FPDM harness and connect JMS FPDM splitter.

6. Run new JMS FPDM harness up to cab. Wire goes above gas tank, around fuel filler neck and between the bed and cab. There’s an oval rubber grommet that perfect for the penetration into cab.


7. Pull all the slack into the cab. You don’t want to zip tie wire loom outside the cab. Tuck it later behind the seat. Lay truck bed back down and install bed bolts. Gave it about 4 ugga ugga in the impact.


8. Now is a good time to install your preferred ground terminal and wire loom to the JMS ground wire, place the JMS under the seat and run the ground wire under the seat and up the back of the seat. The ground wire is NOT ran under and behind the carpet. You will cut a hole as shown in the picture and place the JMS ground lug on the preferred truck ground lug I show in the pictures.


9. Now you’ll run the FPDM wires as you wish and Reinstall the carpet back, amp, and sub. How I did it is shown in the pictures. Tuck, hide and ziptie as you wish. There’s a good amount of room and it’s common sense. Don’t panic, once you’ve gotten this far, you’ll realize I don’t need to tell you how to do it, you’ll see how you want to do it.


10. Now you’ll want to remove your drivers side front and rear trim step caps. You’ll expose a wire tunnel that’s perfect to run the signal wire up to the gas pedal. This is a good time to bust out the vacuum and get this area clean while it’s open.

11. Start from the rear and work up, feed the signal wire up to the front, peel back the carpet as needed and get it up to the gas pedal with a little slack but not too much.

12. Remove OE wire harness from gas pedal and connect JMS splitter. The splitter connects to the OE harness, Gas pedal and red signal wire.

13. ReInstall carpet, trim and tuck wires as you wish. Pretty straightforward and easy task no special instructions needed.

14. With the JMS under the seat, connect your harnesses to the JMS, tuck you wires and use the include self tapping screws to permanently secure your JMS if you choose too. I decided I’m going to try heavy duty Velcro. If that doesn’t work, I’ll screw it down too.

15. Set voltage as shown in pics. Provided by Goose. Start and test run truck. Green light should be on.
 
OP
OP
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Joined
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Yes. Excellent writeup. Great detailed pics. But I’d appreciate knowing what it is and what it does.
It amplifies the voltage to the fuel pump to increase flow. The signal wire and toggle switches steps the current in stages and increments based on pedal input. Helps supports mods like bigger turbos, bigger injectors, HPFP, and E85. All of which I have done except the HPFP. I did an in tank fuel pump mod but it was a disaster and this was way way easier. Stock fuel pump should be capable of around 650-700whp with the booster on e85 and injectors. When I get my dyno time in, I’ll know for sure first hand and will report back.
 
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