DIY : PTFE line- tank to HPFP + inline fuel filter upgrade

doublespaces

Administrator
Oct 18, 2016
7,239
AZ
Is there any word on the difference between 1M and any other fuel rail version? Just curious if the drilled rail is necessary with a stock hpfp.
 

Panzerfaust

Sergeant
Jul 3, 2018
457
Chicago
So my apologies for the bump and stupid question, but I'll be done a short line replacement + HPFP filter removal in a day or two here.

How do you ensure you dont get fuel spray all over? Obviously when doing anything gas or oil line related its smart to have a rag on top and underneath to catch the excess, but what about built up pressure? Do you guys pull the fuse for the LPFP before doing this? Just let the car sit overnight? Or is there some form of check valve that I'm too blind to notice that will stop the car from giving me an ethanol bath?
 

doublespaces

Administrator
Oct 18, 2016
7,239
AZ
Unplug LPFP under passenger rear seat. Wait a day or so. Bring a rag.

Honestly I've never really had an issue but let pressure bleed off a bit first.
 

NoQuarter

Captain
Nov 24, 2017
1,048
Indiana
Disconnect battery

Tap top of each injector with a wrench to remove pressure

Wrap a cloth over hpfp fuel fitting, release slowly.

On low side, same thing with the cloth. There is not a lot of volume once you catch the initial pressure release in the towel.
 

Jeffman

Captain
Jan 7, 2017
1,005
Better: pull out the fuse to the lpfp behind the glove box. Attempt to start the car. This will zero the pressure in the fuel line as the engine starts for 1 second and stops. You’ll get a code and dashboard error light, but this is easily cleared via MHD or scan tool. After doing this, disconnect the battery and resume your work.
 

Panzerfaust

Sergeant
Jul 3, 2018
457
Chicago
Better: pull out the fuse to the lpfp behind the glove box. Attempt to start the car. This will zero the pressure in the fuel line as the engine starts for 1 second and stops. You’ll get a code and dashboard error light, but this is easily cleared via MHD or scan tool. After doing this, disconnect the battery and resume your work.
Thank you, unplugging the LPFP fuse and starting the car seemed like it'd be the best option but I wasnt 100% sure on unplugging the battery or not as I never have with any LPFP upgrades or when i did my BL coils (or anything else requiring me to run wiring for that matter) but I'll do it just to be safe since fuel and electricity isn't a fun combination.

Thanks guys, much appreciated! I may be doing a full write up of how I'll have my system set up if anyone is interested since I'll be doing a hybrid of different methods using parts I sourced from a few different vendors to save some cost that comes with N54 fueling upgrades when packaged together, and I plan on having everything in the engine bay rather than under the car for the other DIY'ers without access to a lift.
 
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