Duramax fuel rail pressure. Commanded pressure stays high.



Duramax fuel rail pressure. 6L Duramax with this combo kit, featuring a brand new GM fuel rail pressure sensor (12686809) and matching GM pigtail connector (85518225). Rail pressure is showing less than 500 on cranking and 178 with key on, engine off?? Haven not logged it driving yet to see if its keeping up with demand under pressure. 4kpsi Your lift pump should be putting out about 10psi, much higher than that can cause problems. The first time I hammer on it for the day, fuel rail pressure jumps to 26,000 for about 2-3 seconds, but then falls off to 10,000 and won't come back up. 6L L5P/L5D Duramax engines. During cranking fuel rail pressure builds up quick, well past 50 Mpa, and follows right along with the desired rail pressure. I then purchased a pod from Banks to monitor the fuel rail Jan 16, 2018 · Wonder if anyone can provide a link or image of the diagnostics steps to be taken by a tech when the P0088 "High Fuel Rail Pressure" code is set? Long story short, I threw this code on my 08 3500 Silverado LMM 222k miles while at the farm and after much research and going as far as I could Apr 11, 2024 · Get a grip on your vehicle's performance by unraveling the mysteries behind the P0191 code - the key to resolving fuel rail pressure sensor issues. I use my Edge CTS to monitor the pressure and at idle I fluctuate between 4. Sep 7, 2019 · 2005 LLY Fuel Rail Pressure Issue Jump to Latest 12K views 10 replies 5 participants last post by ThatWhite_LLY Jul 25, 2022 C Your Duramax shows a P0191 DTC, it means the error titles as “Fuel Rail Pressure Sensor Circuit range/performance. And it still throws the Mar 22, 2015 · Sorry to derail but what does a relief do and how do they go bad? a fuel pressure relief valve (fprv) is installed by the factory to open up when the rail pressure gets above a certain psi. -Identify symptoms of low fuel pressure or high fuel pressure issues. Pressure information from the FRPS is sent to the ECM and the ECM sends signals to the FPR telling it what pressure to allow into the fuel rail based on a host of different pieces of information like temperature, boost Jan 2, 2018 · Hi everyone , my 2004 lb7 has been diagnosed by my mechanic as having a bad fuel rail pressure sensor , ive ordered it online and just got it in today . Part Number: 19300397 Package included: 1x Connector +4 Heat shrink connectors This replacement kit is categorized as a fuel injection part, and air & fuel delivery part, making it a vital component for your vehicle's performance. Feb 8, 2025 · On a 2016 Duramax, the fuel pressure sensor is located on the passenger side fuel rail, typically underneath the EGR cooler; essentially, it's situated on the fuel rail towards the front of the engine, accessible after removing some intake components for better access. Fixed a power wire to my MAF and started getting P0089, 0090 and 00103 immediately afterwards. Can someone give me some insite on what it should be at idle verses going down the road at whatever rpm's? Feb 17, 2020 · Anyone run into this on a l5p? Fuel rail pressure performance during deceleration. Nov 10, 2011 · Two Fuel Rail Pressure Regulators (FRPR) are used. 6L engine utilized a sensor with a steel washer which sealed the sensor to the function block. Data shows rail pressure bouncing 3 to 4k during 0% throttle deceleration. 5K which is pretty quick. Took it back 2 days later. Feb 3, 2023 · I believe thats for the fuel rail pressure sensor, I though it was it but its not. Sep 22, 2020 · The Fuel Pressure Relief Valve should be opening a little above 26k so I would find it hard to believe you’re actually getting to 28k rail pressure. com Apr 30, 2022 · Alrighty here goes nothing… My idle fuel pressure is at 9,000 psi I have tried commanding it higher or lower with my tech 2 to no avail. Disconnect the fuel line at the CP3 and put a LITTLE pressure in the fuel tank, use a rag around the air line- check for flow out the hose. Lastly I installed an Air Dog FP-100 Lift pump with a Sump and also ran my feed line directly to the engine inlet, therefore bypassing my stock fuel pickup and fuel lines that are prone to give Nov 19, 2019 · The SP Tools Duramax Fuel Pressure Release Wrench, No. If additional debris that can NOT be picked up with a magnet (Contamination) is found on the Fuel Pressure Regulator 1, Fuel Rail Pressure Sensor, and/or Fuel Pressure Regulator 2 (Pressure Relief Valve), refer to PIP5370 and Contaminants-in-Fuel Diagnosis. I primarily work on powerstrokes but want to make sure im not missing something. I was curious as the fuel rail pressure. 6L Duramax Diesel Engines Rail Pressure Readings from 0 to 30,000 PSI - 2-1/16" (52mm) Gauge with Black Dial, Clear Lens, Illuminated Red Needle & Digital Display Double Vision Display Eliminate guesswork and fix common fuel system issues on your 2017-2025 L5P 6. It can take some time for the ECM to alter the rail valve current to bring rail pressure into check. Nov 10, 2024 · Ok. This Rail Pressure Sensor has a Scale hieght of approx. The fuel rail pressure at startup barely reaches 1500 psi, but once it starts, it runs just under 5000 psi at idle and up to 26000 psi while driving. I have been trying to figure out a pattern for when it happens, and it seems like it only happens when I am slowing down and almost at idle. Since it's a sensor, the code might clear on it's own, not sure. High fuel rail pressure in the Duramax L5P can cause hard starts and stalling. What should the fuel rail pressures read? I have a Snap-On Delux Dec 31, 2024 · Then we got a low fuel rail pressure code and we changed a frc valve on the cp3. Let’s walk through what each code means, why it happens, and how to actually fix it — not throw parts at it. I purchased a 2019 Chevy 3500 with 51,000 miles. What causes this aside from the fuel filter? Never did it before, could the pump be getting weaker with miles? Truck was running an edge juice, level 1, has no lift pump, and 35 inch tires. Sent from my SM-G960U using Tapatalk Dec 20, 2015 · 1) Low pressure regulator (say 5-7 psi) and pressurise the fuel tank while looking at all the fuel lines under the truck and around the motor. The injectors have a piezo stack instead of an electromagnetic solenoid. I use diesel and have a brand new engine. Dec 26, 2015 · 1) Fuel pressure regulator (FPR): Map actual versus desired rail pressure, if the graph is wavy and there is no air in the system it is usually caused by a bad fuel pressure regulator. my concern is I cannot locate the the pressure sensor on either fuel rail and oddly enough there isn't a video showing a location or Feb 6, 2023 · Hi Guys, direct me if I’m posting in the wrong area but trying to find answers. 2 and 4. The ECM supplies pulse width modulation to change the duty cycle of FRPR2 to Jan 15, 2014 · I just purchased an 06 GMC that had a lot of water in the fuel and wouldn't hardly run . Had a “change fuel filter” on the dash so I swapped the filter Jun 30, 2024 · A high pressure return rate test requires graduated cylinders, a scan tool to command max pressure from the injection pump and a way to plum the return side fuel from the injectors into the graduated cylinders. The truck surges/hunts at idle like an FPR going bad. Shop at DmaxStore for your Duramax needs. Oct 31, 2016 · P0087; fuel rail pressure is less than 22. High pressure fuel is controlled by the ECM, fuel pressure regulator 1 and fuel pressure regulator 2). OEM BOSCH Fuel Rail Pressure Sensor (LLY) SKU: 0 281 002 863 / 98006101 / 97361561 Fits: 2004. Sep 13, 2024 · From Chevrolet-GMC Diesel Diagnostics about LML engines: Verify the fuel injector return line pressure is greater than 3 BAR (see “Fuel Injectors” for more information). Most fittings auto part fittings cannot handle that high pressure. Truck has been running great, occasional lope from the different FPR but thats it. 5-2005 GM/Duramax Pricing: $199. pdf 510. If it doesn't clear on it's own, Key off, clear the code, then see if it starts and runs OK. The rail pressure is high- idle around 5k. Mar 8, 2017 · I'm curious to what my fuel rail pressure should be at , at an idle and under acceleration? I've read plenary of mixed answers, or answer close but not Customer: 2012 LML with no fuel rail pressure. Jan 17, 2013 · I did the return fuel test on both banks and all came back within spec. The fuel pipe fitting was so tight on the adapter that when I finally broke it free I found that it was the adapter that was unscrewing from the injection pump. Fits: 2017-2023 GM/Duramax Includes: Fuel Pressure Relief Valve on the rear of driver side fuel rail Aug 22, 2019 · Recently purchased a 2002 Duramax with tons of issues so far. Apr 29, 2025 · Start up, idle RPM/rail pressure for a few seconds, then the actual rail pressure will drop to about 2000psi, creep up to 20,000psi and level back out at normal idle. That didn't fix it. Cross Sep 12, 2017 · I hooked up my scan tool after confirming the lift pump was working and watched the Actual and Desired rail pressure PIDs. Jul 30, 2023 · I’m changing out the fuel rail pressure sensor on my 2018 l5p. They cleaned out a corroded sensor and Apr 6, 2019 · I saw somewhere that desired rail pressure at idle is 5250psi or something close. If you are running a 200gph pump, you will have more flow than you ever need. I am getting p087 code- low rail pressure. Fuel rail sensor. Mar 2, 2015 · Truck is an 06 LBZ came in to the shop with low power in the higher rpms. Correction 5652223 Jun 2, 2023 · Where is the fuel rail pressure sensor located 2016 Duramax? The sensor is mounted on the right fuel rail under the EGR Cooler. For LLY, LBZ, LMM, see Enhanced Injector Return Flow Test above also. The FPRV is a plug looking part that screws in the back of the driver's fuel rail. It’s not a 10 minute test that anyone can do from home. Jan 7, 2016 · Ok so I am relatively new to diesel performance. The GM 12686809 sensor is a direct OEM replacement designed to restore accurate fuel pressure readings to the ECM and resolve drivabi Oct 2, 2018 · I've read a bunch of fourms but none seem to be quite like my situation. Like your water heater valve, it's not supposed to let fuel through. ? would i tell if im starving my truck for fuel if the May 5, 2021 · Hey y'all! Got a question on the lml fuel system So I replaced the engine in a 2015 lml with a 100k mile engine. Built steering, braces, hidden winch Sold-2003 Chevy 2500HD dmax edge w/ attitude, AFE intake, full exhaust The LML Duramax fuel pressure sensor is one sensor that can be a pain to get to with standard wrenches and sockets, so Merchant Automotive has developed a solution to allow for easy removal and installation of an LML fuel rail pressure sensor. The injectors have a hollow check ball that holds high pressure fuel until the fuel solenoid is actuated by the ECM, this allows The fuel pressure regulator in the high pressure pump and the pressure regulating valve in the rail control rail pressure. It has a lbz engine. Let’s dive into the causes Jan 24, 2024 · Note that the fuel rail pressure is at 24,053 psi . Mods: Stock truck to the Apr 15, 2025 · A fuel rail pressure sensor monitors the diesel engine’s fuel rail pressure. Never a single problem with it until lately. I want to see what mine is by reading it with the cts but I really don't know what is low or high as far as the numbers go. Commanded pressure stays high. On my truck, I notice what sounds like May 28, 2015 · The Duramax uses the injection pump to pull fuel from the fuel tank, through the filters and into the pump. I changed the sensor and harness and the problem was still there. His balance rates are all within GM spec. Since then the fuel tank has been drained and cleaned new fuel pump installed in the tank , all 8 injectors were replaced , new injection pump and fuel rail pressure regulator and sensor replaced . Truck runs great and I just can't figure out what the deal is. 2003 LB7 215,000 or so miles. Jun 11, 2012 · '05 DuraMax (LLY) box stock. 2005 GMC Topkick Aug 25, 2024 · These steps can help maintain optimal fuel system performance and prevent issues like limp mode or low fuel pressure. When this component fails, performance suffers without warning lights. This is the exact wording for the procedure I used, and comes from Mitchell's On Demand. Correction 5652223 Nov 26, 2012 · Now drive the truck hard-- with several wide open runs-- if there is any fuel in the bottle the FPRV [fuel pressure relief valve] is leaking main pressure from the fuel system. The high pressure pump is timed so the peak pressure pulses match the injection events. That makes me think the rail pressure sensor is going crazy. Mar 22, 2022 · I bought a used 2018 2500HD Duramax L5P and a week after owning got a reduced engine power warning and got it scanned and received the P0191 code and took it back to the dealership to address. Desired at 10200 and actual will bounce 9 to 13k. Using conventional wrenches and sockets, a tech needs to remove the EGR cooler and heat shield (s) to gain access to the sensor. If the desired is staying fairly steady and the actual is bouncing a couple hundred psi, then it can cause your rough idle. Jul 13, 2010 · I need to test the fuel rail pressure on a 2006 GMC Sierra 2500. And replaced all injectors. What do y'all think? Jul 17, 2021 · Hi Everyone, I'm having trouble finding any information/diagrams on the location of the fuel rail pressure sensor. Feb 13, 2022 · However, after priming the fuel system + bleeding the air and trying to crank it several times, the fuel rail pressure will only stay around 200-300 psi. 6 duramax diesel? Feb 16, 2011 · Ported Rail Fittings 3/8" Return Line from the motor to the tank I don't get a low rail pressure code or anything just loss of power at the higher rpms, it just doesn't want to pull at all once it hits 17. 5 LMM trucks, and 2) the injector return rates become excessive only under heavy, hot load. same ones i always use and i revalidated them a couple times to make sure. It pulled p0191. Install the female plug into the trucks male wiring harness. 5 MPa at more than 600 RPM, fuel rail pressure too low. This guide will cover fuel rail pressure sensors, including their locations and maintenance. ⇒ It may be necessary to use the terminal test kit with dielectric grease on it and apply/drag each terminal a few times. FASS pump, so I doubt it's that. New to the Duramax. In my log it will show 26107 desired and 29000+ in actual which is over 200 MPA. Does the actual fuel rail pressure more than 175 MPa? Yes? Replace the fuel rail pressure sensor No? Test the fuel rail pressure sensor signal circuit for a short to ground. Its popular among high performance builders to put this sensor in place of their LLY or LBZ OE sensor. Signals the PCM to monitor fuel supplied to the engine Designed to accurately monitor fuel tank pressure Manufactured to GM OE specification for fit, form, and function Sep 12, 2007 · Hi folks, new the forum and looking for help. 6L LB7 Duramax Diesel Fuel Leak from Fuel Rail Pressure Sensor . Both trucks have ~220,000km, my truck has all new injectors but his doesn't. Key points about the 2016 Duramax fuel pressure sensor location: Fuel rail placement: The sensor is mounted directly on the Mar 31, 2014 · I have a 2006 LBZ that just rolled 100,000 miles. Relatively stock truck, intake, exhaust, efi Hooked my AE scan tool to the truck and took it for a test drive immediately noticed the Apr 23, 2010 · Rail pressure is nice to know for tuning your truck and fuel pressure lets you know when your cp3 is starving. I disconnect the FPR no change. I had the connector replaced in April due to P026D. Aug 11, 2014 · They should follow each other at first, but the ECM should begin to correct after the rail pressure actual doesn't follow desired. No cel though. 6 Duramax engine. The high pressure fuel is supplied to the fuel injectors (1) through Sep 24, 2007 · 06 GMC Duramax LBZ SLT White Crew Cab 4x4 fully loaded w/ sunroof Headgasket at 60k PPE Pitman/Idler Arm Brace Kit, Capped Resonator, EFI Live Trippin Switch Mount (black) SC III and Precision ML Converter:sheephump TREX Billet Grille, Anodized Black GMC emblem 4'' Turbo back no muffler and the kitty died Alpine w205, Alpine amp,3 jl10w3's behind seat 5% tint, Billet 9'' antenna 10,000k HID Oct 7, 2017 · My supposition is that A) '09 software has a lower tolerance for lower than requested rail pressure than my '07. My cts only reads anywhere from 10K to 16K is the most I have seen. driving, to a max of 26k. Then see if rail pressure will reach 21,000 PSI at idle, if it does then the low rail pressure under a heavy load is usually caused by a bad high pressure pump. Jul 22, 2020 · Can anyone tell me the minimum and maximum fuel pressure specs for a 2008 chevy silverado 3500 6. Dec 15, 2024 · LML fuel pressure reaches 28,000 - 30,000 psi! I think your rail pressure sounds normal, some others might chime in with what they see. Mechanic's Assistant: Have you checked the engine's fuel supply? Are the fuel pump and ignition system functioning properly? Nov 21, 2024 · About this item Fitment: Fuel Rail Pressure Sensor Pigtail Compatible withChevy and GM 2017-2024 vehicles with the L5P Duramax 6. Many just increase the pressure with a couple washers, to help hole the pressure. The injectors have a piezo stack instead of an electro-magnetic solenoid. Jun 25, 2022 · I have a Lmm duramax swap that I am having high fuel rail pressure at idle 12-18k. Is there a minimum rail pressure requirement during cranking before the ECM starts injection? If so what is the spec? Is the big brass schrader valve at the top front of the engine low pressure or high pressure (rail pressure) fuel tap? May 11, 2025 · These low fuel rail pressure codes are some of the most common, most misunderstood, and most misdiagnosed issues on 2001–2016 Duramax trucks. Pressure is not what is needed from the lift pump, flow is what is needed. Mar 3, 2013 · 2. Please check the part Apr 15, 2025 · Looking for some insight with a problem I’m having with my 2017 L5P with 220k on it. I’ve got a 17 L5P that falls on its face at or close to WOT. Feb 27, 2021 · For instance, if all the injectors passed the test, but the ecm wasn't commanding enough fuel pressure to fire the injectors in the first place then that would render my test pointless because injectors weren't seeing proper flow pressure from cp4. Drove 200ft popped on in limp mode. Code reader says P1089- fuel rail pressure on deceleration. FPR is usually the culprit in that case. The dealership said the fuel rail connector had been changed Jun 11, 2022 · Diagnosing low fuel pressure fuel rail pressure fuel rail pressure to low injector advice lift pump limp Jump to Latest 11K views 16 replies 7 participants last post by Ron Nielson Jun 11, 2022 Cherry_LLy Discussion starter Nov 11, 2013 · About this item MaxTow Fuel Rail Pressure Gauge Displays the Amount of Pressure Running Through Your Diesel Truck's Fuel System - Compatible with 2003-2018 Dodge Ram 5. In the process of inspecting and diagnosing the issue I discovered that the supply line was kinking and collapsing Jul 2, 2016 · I'm curious to know if there is a range for what fuel rail pressure should be at an idle? My pressure is 4500 and my buddy's LLY is 5200. 6L LB7 Duramax Diesel Fuel Leak from Fuel Rail Pressure Sensor - fluid smoke #PI01312 - (08/20/2003)6. 00 Nov 25, 2018 · OK here's the situation 2012 LML bone stock 180xxx cp4 grenades like usual. It measures the fuel pressure and sends data to the engine control unit (ECU). Fuel pressure is steady around 60 while normal driving. Fuel filter has 54% life left and it’s the AC Delco filter. Observe actual fuel rail pressure with a scan tool. The fuel pressure regulator in the high pressure pump and the pressure regulating valve in the rail control rail pressure. New 45% SAC injectors and LBZ FPR installed about 5,000 miles ago, FASS 150, Sump, Cat Fuel Filter. Fuel pressure regulator (FPR): Map actual versus desired rail pressure, if the graph is wavy and there is no air in the Feb 23, 2016 · Checked fuel rail pressure and it was under 250PSI. Jul 7, 2021 · I have a 2015 lml and I’m getting a p0087 low rail pressure code under hard acceleration, rail pressure stays with the desired pressure until 23,000 then the desired will go up to 29k as the actual rail pressure won’t exceed 23,500. Using the PIDs on efi live software labeled "Fuel Rail Pressure" and "Desired Fuel Rail Pressure". I was wondering how involved changing the fuel rail pressure sensor is? I'm just worried about leaks, residual pressure in the system, what's the Jun 6, 2010 · Step 2 Disconnect the fuel pressure sensor and plug in the mail fuel pressure plug to the female fuel pressure sensor. If Oct 5, 2016 · High pressure fuel is supplied through the high pressure fuel line to the fuel rails and then through the fuel injector lines to the fuel injectors. Is this normal? I’ve also noticed if I unplug the FPR my fuel pressure does not go to full rail, but something like 14KPSI. It ran great for a while and now it is back to cutting the power off at 2000 rpms. I personally tested the Duramax fuel rail pressure sensor location and found it to be conveniently located for easy access. Sep 14, 2024 · How Do I Know If My Fuel Rail Pressure Sensor Is Bad? To determine if your fuel rail pressure sensor is bad, check for engine misfires, rough idling, or poor acceleration. Jan 9, 2012 · Been looking around on the interwebby and not finding much on the issue i'm having with an 02 LB7. I don’t have a monitor on mine yet. The truck High Pressure Common Rail Basic Information The high pressure pump builds rail pressure and delivers it to the fuel rail manifold where it flows through the injector lines to the injectors. FRPR1 is still located on the injection pump as on previous Duramax engines. Took it in yesterday morning and did manual Regen, checked fuel filter and cleaned it out, tried tapping around some connectors and wires to trip it and no luck. Begin by inspecting the fuel pressure sensor and fuel pressure regulator for faults or incorrect readings. 5, warmed up. Look at your logs and where the rail pressure is high add some rail valve current to reduce pressure. While monitoring on my CTS3 - in 5th gear at 1900 rpms, desired and actual fuel rail pressure climb to 22k Oct 12, 2012 · Does anyone know what the fuel rail pressure should be at idle? Apr 25, 2024 · Discover how fuel rail pressure sensors work in diesel engines, their role in performance, and troubleshooting tips to ensure optimal operation. It's a 2012 Chevy 2500 HD with a 6. Aug 18, 2012 · At the end of the high pressure fuel pipe opposite from the fuel rail fitting end there's a threaded adapter between the fuel pipe and the injection pump. I was dealing with diesel dilution in the oil. Jan 19, 2019 · The regulator should be able to maintain pressure within 200-300 PSI of desired ideally. 7L Cummins & 2002-2018 Chevy/GMC 6. Apr 2, 2024 · Yearning to uncover the mystery behind P0191? Discover essential tips for troubleshooting the fuel rail pressure sensor in this comprehensive guide. ONLY do this for a short period test. No Check Engine Light. Repair your 2004. FRPR2 is located on the front of the left fuel rail. Description 2017 – 2023 6. CEL recently comes on. I see around 10 or 11 psi fuel pressure and when I'm gettin on it drops to around 2. If you drill and tap the fuel rail, you may develop a leak and it be difficult to fix. i have replaced the fuel rail pressure sensor. The injectors have a hollow check ball that holds high pressure fuel until the fuel solenoid is actuated by the ECM, this allows Sep 2, 2015 · I have a 2011 2500 and it keeps throwing the code for the fuel rail pressure to high. Fuel rail pressure drops way off. The fuel pressure regulator in the high pressure pump controls rail pressure. Wondering how to resolve low fuel rail pressure in your Duramax? Discover essential troubleshooting steps that could get your engine running again. What are the advantages to a higher frp and what Jul 21, 2022 · I’m looking for some help diagnosing a difference in desired vs actual fuel rail pressure in 5th gear while towing a 8500 lb travel trailer at 65 mph with my stockish 07 LBZ w/ 255k miles. After a week of owning it, it through a code p0191 for fuel rail pressure low. 2) Bottle test to make sure relief valve hasn't failed. Got some grief but they supposedly replaced the LH Fuel Rail & Pressure Sensor after 3 days in the High Pressure Common Rail Basic Information The high pressure pump builds rail pressure and delivers it to the fuel rail manifold where it flows through the injector lines to the injectors. I can see the truck is asking for 21000 at WOT and only betting about 8000. Buy LML Injector Return Rail You would inject about 50 lbs of compressed air into the injector return line while cranking to create this pressure. 31,000psi. Jan 27, 2025 · If you own a GM Duramax (especially L5P or LBZ models), seeing the P0087 code (“Fuel Rail/System Pressure Too Low”) can feel like a gut punch. My truck is as listed in my sig. Drove the Instructions for replacement of Rail Pressure Sensor on Duramax LB7 6. Surge or Lope at idle. Things I’ve done: Replaced fuel filter Checked the fuel rail pressure sensor plug. Jul 22, 2024 · In diesel and some gasoline vehicles, a fuel rail pressure sensor (not to be confused with a fuel tank pressure sensor) monitors delivery to the injectors. Fuel pressure will go to about 28,000 psi or so when it Dec 11, 2024 · Attachments Fuel Rail Pressure Sensor Replacement. Jan 2, 2013 · Here recently my truck has been throwing P0088 Rail pressure too high codes at random. May 12, 2016 · Trying to figure out why my fuel rail pressure is so much higher than commanded. When it was cold at idle in park and i first started it the Actual Rail Pressure was at 18,000 when it is being commanded to less than 6000 Jul 12, 2025 · Just purchased a 2018 chevrolet duramax only 40k miles. Mechanic's Assistant chat Customer: My 2011 LML Duramax won't start. I have removed the cold air pipe and Dec 10, 2023 · Replaced the fuel pressure regulator at the fuel rail (drivers side by the firewall) and haven’t had the code come back. But what happens when the sensor fails and how will you know? Keep reading to understand the signs of a bad fuel rail pressure sensor, what causes it to fail, and how May 1, 2015 · desired fuel rail pressure vs actual fuel rail pressure I have a stock cp3 and injectors on my 05 lly, if I really get on it my desired fuel pressure will be around 23k my actual will stay there for a little then drop down. Oct 7, 2015 · So I see a lot of folks talking about rail pressure. 14400, features a two-piece design to remove the fuel rail pressure release valve sensor on 2011 and later Duramax LML engines. Jun 4, 2021 · Are you asking for the fuel rail pressure at idle or fuel pressure from the lift pump at idle? The LML has an idle FRP of 4. If I disconnect the Fuel Rail Pressure Sensor I am then able to command a change of pressure with my tech 2. Took it to chev dealer & said #1 injector was low but in spec so they replaced it. But (here's the weird part) after it does The fuel pressure regulator in the high pressure pump and the pressure regulating valve in the rail control rail pressure. This solenoid is normally open. New cp4 and injectors from bosch new lines cleaned everything to do with fuel system install fass lift pump prime system no rail pressure. 0 duramax - didn’t pull new travel trailer well. Highest is still 180 MPA I bought a used 2018 2500HD Duramax L5P and a week after owning got a reduced engine power warning and got it scanned and received the P0191 code and took it back to the dealership to address. My 13 Duramax with 180k miles. If the Feb 24, 2022 · See this: GM 12651990 LML Rail Pressure Sensor 2011-2016 Duramax As you can see, there's not much to the sensor itself as far as installation. This issue is notorious in Duramax engines, often linked to failing CP4 pumps, clogged filters, or sensor errors. Probably due for a filter change, and an injector or two are a little noisy. Diesel. Your truck will need the tune edited to rescale the pressure readings. As stated previously, the fuel pressure with the Ignition relay unplugged needs to be a minimum of 2500 to 3500 psi during cranking for the return rate test results to be valid. If you have EFILive if you don't have it already, you can download EFILive and a stock LB7 tune and take a look. Feb 9, 2016 · What PIDs are you using to read actual and desired rail pressure? Maybe the PIDs need to be revalidated. I have since replaced all rubber fuel lines around the filter head, replaced the filter head + filter itself, and tried shimming the FPRV but am still stuck at a FRP of 200-300 psi. This whole evolution always happens within ~25sec of initial startup. During the "ebb and flow" of the idle, rail pressure is anywhere from 4600-5200ish. . If you have a rough idle, poor fuel economy, and low power, this may be the fix. 3 - 4. Includes the Fuel Pressure Regulator which is not sold separately by GM. Apr 30, 2015 · I was just wondering what "normal" fuel rail pressures are at idle. All stock. I see guys on the forum stating 20k + for their frp. May 31, 2018 · New to the site. I just installed a new fass 150 on it also? any ideas why I cant hold Bulletin No. I have been getting a reduced power warning and codes P228a-c but only when towing. The mechanic should know that the crankshaft snapped, I have a rebuilt engine, and new injectors since the old ones had high leakdown. Low fuel rail pressure cripples performance, causing rough idling, hard starts, or even engine shutdowns. Everything I have read says to look at injectors first, then CP3. There’s no debris on FPR1, and I’ve also installed new rails and lines along with a rebuilt filter head. 6L Duramax L5P Driver (Left) Side Fuel Rail Assembly with Regulator OEM # 12686810 / 2439 Direct replacement left side Fuel Rail Assembly. Genuine GM New Fuel Rail Pressure Sensor For 2011-2016 GM 6. Silverado, Sierra 2500 HD. I have my desired flow set at 26110 which is just over 120 MPA. Bypass the fuel filter housing with a hose and see if the concern goes away. 6L LML. Oct 29, 2021 · While diagnosing the the fuel system low rail pressure issue I actually found something that nobody ever mentions. When servicing the vehicle with the VIN you entered, the following diagnosis might be helpful if the vehicle exhibits the Just got this same issue on Sunday after filling up. See full list on carfluidpro. The sensor is mounted on the right fuel rail under the EGR Cooler. Gonna Oct 21, 2020 · Here is some info of my Duramax 2008 LMM 177k HSP egr delete and Y bridge Fass Titanium 165 S&B cold air intake Kbdp hot side intercooler pipe Race fuel rail plug Ported fuel rail fitting EFI tuning (Big Twin Diesel) Flopro 5” exhaust MBRP down pipe Pcv reroute Resonator delete Beans fuel sump Thanks in advance! Bulletin No. I'm running autoenginuity Scanner to monitor Desired vs actual fuel rail pressure. One week from purchase it threw a P0191 code and then a P0189 code which put the truck in limp mode. That is very high pressure. ? I got the guage so i can see if my ppe hott+2 is runnin the rail dry At idle mines at 6,000 psi what would WOT be. There's a ton of info here but I can't seem to find the answer to my question searching old threads. Got some grief but they supposedly replaced the LH Fuel Rail & Pressure Sensor after 3 days in the Mar 23, 2024 · My desired pedal position and actual match pretty closely, and my fuel pressure desired and actual are within 2MPa of each other, but my FPR duty cycle is always 20-40% throughout the RPM range. 1 KB Views: 12 Ron Nielson - Most of the information I provide relates directly to my 2008 LMM - Your truck may be a little (or a lot) different 2008 Silverado LT, Crew Cab, 2WD,LB . New to the forum and Dmax's in general. I have followed ALLdata to find Jun 29, 2018 · I also ported the fuel rail fittings and put in an new Fuel Pressure Regulator while I had everything just in case that somehow was effecting something. : 20-NA-197 5652222 Inspect the fuel pressure sensor electrical connector for corrosion or damage. You get the truck hot and ask for full fuel it derates and you have to cut eng off for 2 Nov 22, 2016 · I am having max fuel pressure continuously my full rail pressure is 23,000PSI Exergy 60 over Injectors, Sportsman Pump and LBZ FPR all newer less than 4,000 miles. Install video of our LML fuel pressure sensor fooler and delete plug. Despite rail pressure building up the engine will not fire. Feb 17, 2016 · A Fuel Rail Pressure sensor (FRP) is located on the rear of the left fuel rail. Does anyone know the torque specs for the throttle body and the sensor? thanks in advance! Sep 24, 2010 · Now that i found my fuel rail pressure senssor and plugged in my guage What are average fuel rail pressures. Conclusion Understanding the precise location of the fuel rail pressure sensor in your LMM Duramax engine is essential for maintenance and troubleshooting. Jan 10, 2012 · My dads truck towing around 16k pounds up a gradual grade limped for low fuel pressure. Mar 10, 2013 · That is for fuel supply pressure, and can be 10-20 lbs, depends how it is set. Bone stock truck with 143,000 miles. I told him to pull glow plugs and then crank to see if maybe an injector or two were stuck open draining fuel rails. Sold-2012 GMC Denali HD deleted, tuned, leveled on 34s and 20s. The connector body is female (if that makes sense) and the terminals are male. Took it to dealer they changed out fuel pressure sensor and wiring kit. Silverado, Sierra 3500 HD. 5-2010 Chevy Silverado/GMC Sierra 2500/3500HD LLY/LBZ/LMM Duramax with a Bosch fuel rail pressure relief valve. Jul 29, 2015 · Removing and replacing the Duramax fuel rail pressure sensor switch on 2006 - 2010 LBZ & LMM diesel engines is difficult using standard wrenches and sockets. Nov 5, 2017 · Replaced CP3 Injector pump,came with new pressure regulator. I haven't changed my fuel pressure table. I have no stored trouble codes. Any ideas before Chevrolet looks at it? Replacing #2 Fuel Pressure Regulator on L5P Duramax 12-4-2023 Thank you for watching! If you would like to see exclusive, add free content along with early a Apr 6, 2022 · The FRPS is the Fuel Rail Pressure Senso, determines actual fuel rail pressure of course, and is mounted on the fuel rail. Shop DmaxStore for your Duramax needs. The time taken to accomplish Jul 19, 2012 · I have a 2007 chevy 3500 classic. I have put two cp3 pumps in and three pressure regulator and a new fuel rail pressure sensor and still no changes. Mar 11, 2019 · Buy Duramax Fuel Rail Pressure Sensor 8) If these codes set only on hard acceleration or when pulling a hill with a load, check fuel supply issues first. Still Sep 15, 2003 · 6. In both circumstances, the desired rail pressure holds at the normal rate. Do you think my airdog 165GPH is running out of fuel when it demands that much with the preset setting? Sep 18, 2015 · 2024 Chevy 2500HD high country loaded- stock for now sold-2024 Chevy 1500 silverado ZR2 w/ 3. 3) Balance rates on your injectors. Jan 4, 2019 · If you do not have fuel in the CP3 pump- only air- it will NOT build rail pressure. Regulator was very sloppy compared to the new one and I’m sure the fuel was bypassing the o ring. ?? Truck is running fine. If you’re experiencing hard starts, sluggish throttle response, reduced power, or fault codes on your L5P Duramax, the culprit is often a failing or misreading fuel rail pressure sensor. 6L engine. 6L engine with function block The original rail pressure sensor used on the function block of the LB7 6. Note that right means passenger side. Mar 1, 2016 · I believe there is a table in the LB7 and LLY tunes that sets the voltage to pressure of the rail pressure sensor. You should change the fuel filter at recommended intervals to keep the fuel system free from contaminants. When I put the truck back together it seemed to run great but then after about 15 min sitting at idle the fuel Nov 17, 2021 · Introduction: This guide will demonstrate the procedures to install the LBZ/LLY fuel pressure regulator in the LB7 duramax. Still not right. It cranks but wont start and while cranking rail pressure only shows 260-300 I can start it with starting fluid (I know I'm not supposed to) but it'll run on fuel if I keep it at OEM GM replacement fuel pressure regulator for 2017-2023 Chevy/GMC 6. ” Read this article about this code. I have most squared away but im getting a P1093. Found a cracked injector and solved that problem. I am getting fuel returning which seems strange no fuel coming from the pressure -Diagnose potential problems with fuel injectors, fuel rails, and pressure regulators. 9L or 6. Learn more here. The fuel rail pressure is the injector pressure and can be 5k up to 23k. Routine Maintenance Schedule Regular maintenance helps keep your Duramax running smoothly and can prevent the P0087 code. uravyk mkajqsm ixm sfr nobtcs kvoj cyqjc lrl hbqgr qrkw