Fuel Pressure Regulator Location

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ChrisIB
Scoobytruck Lurker
Posts: 9
Joined: Wed Aug 12, 2015 8:49 pm

Fuel Pressure Regulator Location

Post by ChrisIB »

Please forgive me guys if this is already discussed or that I offend some of the Jedi’s. I have a 04 Baja Turbo manual with 101k on the clock. I have a factory turbo with light mods and a safe daily commute open source tune. I recently put in a DW300 fuel pump which I know is more then the OEM but from everything I read you don’t need a tune. My problem is that the vehicle is running super rich. 17.8 idling. I just put in a new turbo inlet because the OEM one’s are prime to leak. From what I read you don’t need a tune for that as well. I recently installed AEM steering wheel mounted gauges turbo and AFR. I’m trying to find the location of the fuel pressure regulator but I’m having difficulties. The Chilton book is much to be desired. I’m prepping to sell this vehicle because I recently just retired from the service and I’m 36 and also I need to get my pool house foundation repaired. Like I said it’s a 5 speed manual with only 101k on the clock. Timing belt and water pump was done at 95k with receipts by reputable mechanic shop. Oil pan gaskets and valve cover gaskets done at 84k with receipts same mechanic shop. Safe and mild tune done at 88k by the folks who won the Pike Peak hillclimb.
Mod list:
Mad Dadz UEL headers
Custom turbo back exhaust 3 inch
MadDadz up pipe
Grinspeed divorces downpipe
ACT preformance clutch with aluminum flywheel kit done at 82k
STI intercooler
No air intake because it’s a mild tune OEM air intake
Subaru B4 Porsche 18 wheels only available in the UK
Subaru B4 aluminum hood
Subaru B4 strut brace Sti
Perrin Pitch mount
HKS blow off valve
Group N motor mounts and tranny mount just installed
I got parts I ordered still in boxes I hardly drove this car it’s sad actually.
Parts in boxes
PTP turbo blanket lava
Grimspeed mastecyclinder brave
Perrin lockdown kit
Cobb shifter front and rear shifter bushings
TIC out trigger bushing kit
TIC shifter Linkage and a bible stack of receipts for auto repair
The sooner I get this fuel pressure regulator replaced the sooner I can sell to y’all.
I’ll send pics along requests
DocSemtex
Scoobytruck Lurker
Posts: 19
Joined: Fri Mar 15, 2019 9:58 pm

Re: Fuel Pressure Regulator Location

Post by DocSemtex »

No worries:
Look to the upper-right of the master brake cylinder and you should notice a few lines coming through the firewall and around/along the strut tower. You should see a skinnier flexie line [evap line] and (2) beefy reinforced lines. These will be your fuel lines and confirm by identifying the pale plastic ‘safety’ clips spanning the couplings. Follow these lines and you will run into the fuel dampener and the pressure regulator.

The dampener is the size of a jumbo marshmallow, enameled black, and looks like it’s wearing a short top hat. Don’t mess with this unless you have serious stumbling and be ready remove both bits and go with a small airplane fuel pressure regulator. They rock.

Seriously.

(The dampener with the weird recirculating design (LGTs) and old OEM fuel lines can sometimes result in a weird stutter around the mid-2ks - some experience at 2600-2800, others 2250-2400. Otherwise, it’s purpose is to keep the fuel pressure from surging. ...Uhm.)

The other bobble is the fuel pressure regulator. It will have one line from the engine, one to the tank, and a nipple for a vacuum line.

Feel free to share any unpleasant experiences while uncoupling the fuel lines. (Hint: cut up a beefy pen to make two half cylinders out of the barrel. Clean up the burrs and give’m a squirt of oil for easy connector removal.)

Now, for your reading pleasure:
//jdmfsm.info/Auto/Japan/Subaru/Baja/2004/Service%20Manual/

Oh, and did you know you can turn your 04 BT ECU into an 04 STi ECU, marry it with an accessport, and use Cobbs flexfuel system? Your Baja is practically begging for it.

-doc (11B3V)

If you are anywhere near Denver, I’d be happy to give you a hand.
05BT5MT 128k sorta stock. Kinda.
06BT5MT “212k”; 8.5:1/E85/28psi; AWIC; RA1-4/LGT 5th; SureTrack LSDs; Haltech
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kamesama980
Scoobytruck Master
Posts: 369
Joined: Mon Feb 29, 2016 6:54 am

Re: Fuel Pressure Regulator Location

Post by kamesama980 »

Flash it into an 04 STI and yes, a cobb would work. Tactrix/romraider supports the turbo bajas now as well. Nothing inherently better about tuning with one vs the other as long as the tuner knows what they're doing.

FYI, if you're looking at AFR, higher numbers are lean, not rich. Where did you install the wideband o2 sensor for the gauge? if it's upstream of the turbo, the manifold pressure will skew the readings and can permanently damage the sensor.

Have you actually checked the fuel pressure or are you just spitballing?
-Russell
"You don't get to judge me for how I fix what you break"
03 sport 5mt
05 turbo 5mt vf39 and other STI bits, 3" turbo-back
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