346750 - Subaru In-Tank Fuel Pressure Regulator Installation
346750 - Subaru Fuel Pressure Regulator
Congratulations on your purchase of the COBB Tuning Fuel Pressure Regulator! The following instructions will assist you through the installation process. Please read them BEFORE beginning the install to familiarize yourself with the steps and tools needed. If you feel you cannot properly perform this installation, we HIGHLY recommend you take the vehicle to a qualified and experienced automotive technician.
Parts List
Tools Needed
Hand Tools
Phillips head screwdriver
Flathead screwdriver
Deadblow Hammer
Misc.
Drain pan
(Probably a vacuum because you know it’s been a while)
Pre-Installation
Park your car in a flat level area.
With your car running, remove the fuel pump fuse and leave the car idling until it dies (this may take a while.) This should depressurize the fuel system to minimize the amount of fuel spilled.
Captains Seat-Equipped Ascent
Slide the Passenger’s side (USDM) rear seat forward as far as it goes (you may need to push the front seat up).
Lift up the carpet between the two seat rails. It may be easier if you carefully remove the trim from the inside seat rail. (Note: The trim clips attached to the trim come off fairly easily on this piece, if they stay in the rail make sure to carefully remove them and re-install them on the trim before installing. If you just push in the trim it will typically break tabs off.)
All Other Vehicles
On the front edge of the rear seat where it meets the carpeting there is a small black T-shaped piece located roughly behind each front seat. Pulling on this will release the front edge of the seat and it will slightly pop upwards. It’s sometimes easier to pull it from both sides as it’s a bit of a pain to pull.With the front edge lifted up, gently pull it forward and disconnect the electrical connector on each side.
Push the seat bottom towards the back of the car and down in order to free the rear seat from the retaining hooks.
You should now be able to safely remove the rear seat bottom from the car and place it somewhere clean and safe.
Now you really should be responsible and vacuum under the seat while it’s out. Get those loose chips and wrappers out of there.
Undo the 4 Phillips screws holding the fuel pump cover in on the passenger’s side (USDM).
Depress the release tab on the connector to remove the electrical connector from the fuel pump hanger. If you’re having a hard time getting to it with the cover in the way, you can pop the grommet out of the cover to move things around a bit more to your advantage.
With a piece of paper towel covering it to prevent fuel from spraying out due to residual pressure, squeeze down the two orange tabs on the fuel line and wiggle it to release the fuel line.
Put a towel or trash bag over the carpet near the fuel pump and to the outside of the car. Taping it down can help prevent fuel from sneaking under.
Using a fuel tank lock ring tool with a 3/8” ratchet push down towards the pump and unscrew the cap, or CAREFULLY using a hammer and screwdriver to tap the ring with a screwdriver, remove the locking ring from the fuel pump.
Lift the fuel basket out a few inches and allow it to drain. As the fuel drains out you can lift it slightly higher.
Once you have easy access to the bottom, squeeze the two tabs to release the siphon pump line from the bottom of the fuel pump hanger. Make sure not to lose that in the depths of the fuel tank as you’ll need to reinstall it in a few minutes.
Remove the fuel pump hanger from the car!
Fuel Hanger Disassembly
With the fuel pump assembly out and drained, we can begin the dissembly process.
Start by removing the wiring from the small retaining clips that hold it in place on the basket.
Now that you have the wiring freed up a little, unplug the wiring from the top of the assembly by depressing the tab and removing both connectors.
Grab a pair of pliers. Gently push down on the top of the pump with your hands and look at the leg of the hanger with the spring. At the very bottom there should be a retaining e-clip. Gently remove it with the pliers and set it somewhere safe you wont lose it. It is absolutely critical to re-assemble the pump so make sure not to lose it!
Slowly lift up on the top of the assembly and then pull it out of the bottom basket. Set the spring somewhere safe as well.
At the bottom there is a hose plugging into the bottom of the basket. Gently lift up on the tab with a pry tool or flat-blade screwdriver and pop that free.
Using 3 screwdrivers or small prying tools you’ll now release the three tabs holding the pump into the basket. It’s easiest to work one free and sort of wedge the tool in place to hold it open while you work at the other two.Sometimes swearing helps. Once those are all lifted up, you can remove the fuel pump assembly from the basket.
Undo the three clips holding the fuel pressure regulator in place. I try to use a smaller screwdriver but wedge it in place to hold it open, though in some cases you can get it to hold open on it’s own.
Once the retainer is removed, gently pull the fuel pressure regulator out. If it’s really stuck, gently stick a screwdriver in-between the regulator and the plastic pump housing and slowly twist. Be careful as using too much force and not enough patience can cause damage to the pump housing.
Once it has popped out a little, you can pull it out the rest of the way.
Left Side - COBB Regulator Marked with COBB Tuning (Black upper seal)
Right Side - Stock Regulator (white upper seal)
Fuel Pressure Regulator Installation
Lightly grease the o-rings on the new regulator with the supplied lube.
Gently push the regulator in to place. Slow steady pressure should get it into place, if you go too fast you could damage an o-ring but it’s not common.
Reinstall the retaining clip onto the regulator. Make sure they’re all completely clipped as you don’t want this falling out.
Reinstall the fuel pump assembly into the basket. Make sure not to crimp any of the tubes inside. If you feel it get stuck or stop, make sure everything is lined up internally before continuing to press. There is a vertical connection the pump assembly has to slide onto so lining that up should help. Make sure all three retainers click into place.
Attaches to Yellow hose connection in basketSlide the spring back onto the leg of the fuel pump assembly lid (the one with the slot for the retaining clip)
Reinstall the lid onto the basket and lock it in place with the retaining clip.
Make sure it moves up and down freely and nothing gets squished.
Plug the wires for the fuel level sender and fuel pump back in, and route the wiring back under all the retaining clips.
You’re all done! Throw that thing back into the car (not literally) and reinstall the hoses, wiring connection, and rear seat.
Links
316460 - Subaru In-Tank Fuel Pump Installation
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