This Sensor Was The Cause Of This L5P's Fuel System Issues!

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[@flynnstone345]

Your 100% right with a the high data system it’s almost impossible to figure out what’s wrong with these LP5’s. The can bus system is wild on them how everything is looped threw everything. Keep the great videos sir..

[@time2grind.entman-man265]

I just changed mine. Idle it everything was fine. Took it for a little drive (light load) everything was fine. When I got on the highway….ALL HELL BROKE LOOSE! I got a major fuel leak smoke everywhere. Towed it back to my shop took everything apart I noticed diesel around the fuel rail sensor (which I just replaced). I checked to make sure it was torqued down, it was, I checked all the fuel hoses around the fuel rail they’re secure and dry. Tightened everything up started the truck I revved it up to 2500rpms nothing no leaks no smoke……nothing. I’m very hesitant about taking back out on the road. Can someone plz help me!

[@adamphares-xp9eq]

I’ve had this same issue with my truck and have not replaced the sensor yet. I do believe it’s the connection in the sensor vs the sensor being bad though. Anytime I feel the issue return I disconnect and reconnect and it goes aways for a long period of time

[@Hogdog970]

i did just the plug, when i first got the code it lasted 20k miles, now the sensor is bad.

[@unapologeticallypatriotic3853]

Alot of times you can pull the plug apart and pinch those connectors down so it's go and connection and it'll remove the problem. Had the same issue with injectors on passenger side. My dumb ass brother in law had same issues and rushed right out and replaced 4 injectors only to have the problem come right back as soon as they were installed so I knew then it had to be the connectors. I pulled the pig tail apart and pinched the pins down and I knew when I felt the firm click after installing it fixed it and the issue hasn't came back since. Been about 20k miles ago.

[@Peter-r1q5c]

@@unapologeticallypatriotic3853 what do you mean pinch the pins down? Please help as I am hoping for a reponse, i’m going threw this BS with my fuel rail pressure sensor. Supposedley.

[@sammythebull2240]

Hey man any chance you can explain where this connector is located? Is it in the same area Denny has to get to in the video, which will mean taking all that stuff out of the way to get to connector to clean it and reconnect?

[@chadkelley5523]

Can you get to the connector and disconnect without taking everything else off? Want to stat with this and see if this will fix my P026D code.

[@_sophia_1765]

Hey brother I changed the same sensor and now when I start it it's hard to start. Any idea? This was the only code I was getting.

[@davecamilleri9411]

I took a trip from Wyoming to Salt Lake City last summer in my 17 L5P. About 200 miles into the trip my wife was spelling me by driving and truck went into limp mode on I-80 while driving 80 mph. Pulled over to the side of the road and read codes on my I-dash and it was low fuel pressure. I had seen this code randomly pop up but usually only when I was towing my 5th wheel with my derringer on level 6. I cleared the code and I took back the driving duty, made it a mile and llimp mode again. This time I disconnected my derringer harness and problem stayed gone for the rest of the trip to SLC. Next day I was running an errand without my wife in the truck so I got on the truck hard and was watching fuel rail pressure on the I-dash and boom, limp mode again. Limp mode is a PIA because you basicly have a dead pedal and the truck will barely make it to the curb. I cleared the code and truck drove fine again. I did a little research and there is a NTSB bulletin for the L5P that has to do with the harness connector for the passenger side fuel pressure rail. Hmmm. I called a Chevy dealer and asked if they had a passenger side fuel rail sensor in stock and he said he had two. I asked if he sells a lot of them and his response was why do you think I have two! I went and bought the sensor and replaced it in the hotel parking lot the next morning before it got to be 100 outside. I have Mitshmoto charge air pipes, so I didn't have to fight the stupid ring in the parking lot, but I had to source a socket for the sensor because I didn't have one with me in my toolbox. I removed the sensor and applied some special conductive grease for electrical connections that a buddy of mine recommended to improve electrical connections. He told me he has to use it on lots of terminals on his Dodge to keep electrical items working. Upon inspection of the original sensor I noticed one of the pins was discolored and I would guess was the culprit. I test drove the truck and it drove good. I reconnected the banks derringer and it immediately acted up. I removed the derringer harness again and put in a call to Banks and they sent me out a new harness. That seemed to fix the majority of the issues, but I still would get a random code for low lift pump pressure and by watching my lift pump pressure on the I-dash I figured out that when I would decelerate like going down hill without my foot on the pedal, my lift pump pressure would drop into the 30's. I ordeded a new lift pump module and lift pump control module. I installed the new lift pump module and problems solved! I got the module because there seems to have been a shortage of them and didn't want to replace the pump and find out I needed the module too. This has been at least 5k miles ago and everything is working perfectly. Truck has 88k and tows a 15k fifth wheel quite a bit. I fought the low fuel rail pressure reading for several years because it would usually only trigger with trailer in tow, derringer on level 6 at WOT.

[@SHEAR-JASHUB]

same issue on my 2018 duramax diesel dually while pulling a 5th wheel- strangely enough... headed into Wyoming from SLC, then southeast to South Dakota while clearing codes all the way until I got it serviced by the excellent techs in Mitchell, SD @ the GMC dealership. It ended up being the wiring harness; which I didn't get the details of but here I am in April of 2023 with a similar issue again. I'm thankful for this video.

[@davecamilleri9411]

@@SHEAR-JASHUB There is a NTSB bulletin for the wiring harness being an issue and advising replacing the connector that goes into the fuel rail pressure sensor. What I found was that due to poor connectivity one of the pins on the fuel rail pressure sensor was discolored and thus intermittently loosing connectivity. If I had an issue with the harness I would also replace the sensor.

[@SHEAR-JASHUB]

@@davecamilleri9411 I appreciate that!

[@lloydlacross1358]

@@davecamilleri9411 been chasing mine . until i hit a bump on my road 2mph definitely a connection issue. went right into derate. cleared code has been fine. had some jerking issues very random. but its making seance. bad connection somewhere

[@trevormerrill9070]

I'm having the same problem with my lp5 17 I have the idash derringer pedel monster random low fuel rail pressure codes they have been happening on start up it would reset I had it come up while driving yesterday and it wouldn't reset so I turned it off for a minute popped the hood tried again and it reset do you think it's the wire harness for the derringer

[@lt1swapgonzalezperez102]

Will this cause the truck not to start?

[@gurgisgutters725]

Mina had both pressure rail sensors need to be replaced. Although it surges and when towing and just idling along at like 1-10% tps

[@mikeohara9282]

What are torque specs for sensor. Replaced but now leaking.

[@ricardomejia8077]

I replaced the regulator now I have a crank no start!

[@brandontyler8523]

i had issues with my truck for 2 years and not even gm could figure it out. they sent an engineer to look at it and he told them to replace everything fuel related. 10k later on them it was fixed and 6 months later it came back. traded it in and went back to a ram.

[@xxxjfranklinxxx2902]

Man I love chevrolet to death ride or die but man this damn 18 duramax has been hell for me lol I’m starting to rethink where I stand lol

[@fredwilliams7893]

I just bought my first chevy! it's a 17 duramax! Should I be worried now? . Lol

[@BradB_Sportscards]

​@@fredwilliams7893Any brand pass 2010 I'd be worried 😅 especially with a diesel engine!

[@fredwilliams7893]

@@BradB_Sportscards you would be right! Post emissions diesels are definitely less reliable

[@MobileAutoElectric]

Fuuuuuuu. 2018 start stall no codes besides crank relearn after customer removed body to replace engine 😂😂😂 Does the chassis control module or the fuel pump control module have communication and live data pids and or codes?

[@abrahamramirez1056]

Hey brotha what are the torque spec for the throttlebody and the fuel sensor please

[@arturogarcia9785]

Did you ever find the torque specs?

[@Jorgemendez-y5z]

hi denny i have 16' gmc sierra duramax lml 6.6l on the screen it has check engine and power reduced it has a code P00C9 fuel pressure regulator high control circuit low voltage, the power is perfect and it walks perfect too i changed the 2 batteries and the filters are changed frequently what do you think, thank you

[@joshbryant7363]

May be worth a try on my 15’ GMC… I have been flirting with a P1089 code FOREVER. It doesn’t go into limp mode though. Finally took it to a mechanic, he changed the fuel filter and said “that was your problem”… well, a few weeks later…no it wasn’t 😂. This seems like a relatively cheap possibility before we start going full fledge injectors😢 or cp4.

[@allamerican7830]

Was the truck going into limp mode?

[@blueman1010]

Hi where did you find this part, I have the same issue and need to replace mine everyone seems to be sold out or trying to sell it for list. Please advise

[@hugocampodonico7719]

What codes did you have?

[@chriswright1527]

I got a problem like this with my 2020 duramax has been deleted tuned and just put stealth 64mm turbo on it and when you pull out it like shuts off and comes back and when in a lug it does it also the check engine light come on said low full pressure need help figuring out

[@bruceshepard1136]

Chris did u figure this out yet? U could try to reach out to your tuner and send the a log file that should give u direction

[@haddonsmith345]

i have a 23 model l5p with a U1345 code. Any idea what this is?

[@danieldelgado3008]

Dtc u1345 is ecm loss communication with a device on LIN bus number 1, there’s three devices on that circuit. The lower grille shutter, upper grille shutter and low temperature coolant pump. I have already seen multiple 23 models in the shop with this same code set. Each one of them has been fixed by the following. Check the electrical connector for water intrusion and corrosion at the lower grille shutter. If water is found in the connector replace the connector and the lower grille shutter.

[@sikc6z415]

@@danieldelgado3008I got a 21 been deleted 40k miles now having damn issue with code U18A2

[@alexanderl7020]

Sensor torque spec? I have it at 60ft/lbs, but i still get a slight RPM fluctuation at idle. 500rpm-600/700rpm.

[@arturogarcia9785]

Did you get the torque specs?

[@mrericescobar]

Denny, can you help me out? Do you know the part number to the cheap brittle grey locking plastic ring? Mine was very brittle and broke as soon as I touched it. I’m on alldata diy and can’t find the part or part number.

[@mrericescobar]

Or if anyone knows the part number

[@markklim10]

Hey please help. I have P018B code on and throws me into limp mode. I changed the fuel pressure sensor on passenger side fuel rail and it still has this issue. Any more advice?

[@unapologeticallypatriotic3853]

Probably need to tighten the pig tail. You can pull them apart and take needle nose pliers to pinch the connectors closed. Seems alot of the pigtails on these trucks have this issue. More frequently on the injector harness passenger side for some reason.

[@sallepre948]

Hey any luck on the issue ?

[@denalihddenalihd359]

What’s the torque

[@Paper4150]

BCM replacement fix the can bus issue you think?

[@josephdinome8611]

I had the same problem, changed that fps, put a new pigtail on. Also changed the module in the rear still having the same issue. So weird

[@DennyDiesel]

Check the fuel filter

[@josephdinome8611]

@@DennyDiesel also changed the fuel filter, forgot to add that in. I spoke to my guy could be a possible tuning issue. Truck is at the shop now getting some body work done haven’t had a chance to drive to see if anything has changed.

[@abrahamramirez1056]

What was the torque spec for the FRPS brotha please

[@abrahamramirez1056]

@@DennyDiesel what the torque spec for the fuel pressure rail sensor please brother

[@kentsteinke4211]

What year of truck was that? I have the same issue but mine is a 2018. And they said it was 17 hours labor from the dealer.

[@unapologeticallypatriotic3853]

Takes less than an hour to change it out but while you have it out may want to tighten up the pigtail.

[@rbyronson2426]

Could this issue be the reason why my remote start won’t work too! The dash information said water in fuel, low power mode also.

[@Codysfixations]

Anytime there is a check engine light or even low fuel the remote start will not work

[@jduran7002]

Denny where are you located? I need your help

[@pedromontelongo5367]

Question did you also have U0422-171 code coming up with the P0191-00? I’m trying to diy repair before I take it to the dealer and pay couple bucks.

[@EllisNichols]

I have the same problem. What did you do?

[@pedromontelongo5367]

I parked the truck been out of town working did you figure yours out

[@javiertoscano2886]

What code did you have?

[@armandogonzalez8135]

Where you from I mean state ???

[@GreaseMonkChronicles]

I got p0191 would that be the rail pressure sensor or pressure sensor.

[@elscrappy432]

Did you ever figure it out ? I have gotten that code randomly as well I’ll clear it and it runs fine. I heard it could be sensor or the pigtail

[@jvg9362]

@@elscrappy432did you figure it out by chance? Been having the same issue.

[@mechanic383]

What's the torque specs on this sensor?

[@83chevy1]

Hey bud

[@83chevy1]

I have a question

[@mechanic383]

@@83chevy1 yeah?

[@marcmarion9396]

I fought that damn cheap pipe ring forever before I finally broke it 🤷‍♂️

[@mrericescobar]

Did you find a replacement for the cheap pipe ring. Mine broke as well. Did you ever get a part number for it?

[@Ilikeryche]

I had to stop watching because I already had a cigarette lit and then I saw the stop smoking sign.

[@xtoxicanimalx3501]

Is this a low acceleration fix? My Duramax will NOT accelerate correctly. I can use cruise control to accelerate, the dealership can't find the problem. Occasionally the check engine light will come on and it will run like a bat out of hell. PLZ. SOMEONE HELP ME!!!

[@chrispelkington3188]

Check you accelerator pedal sensor