L5p injection pump problems. Oct 11, 2025 · As a first-generation L5P, these models experienced the typical early l5p production problems. Jan 22, 2025 · Learn the most common Duramax problems for LB7, LLY, LBZ, LMM, LML & L5P engines — symptoms, causes, and solutions from the diesel experts at DPP. Sep 22, 2022 · This article will explore the 6. 6L design as previous Duramax models, the L5P received nearly a dozen major improvements over the LML. First time i've had a problem with a diesel. GM Part # 12678993, 12701094 Denso Part # 294050-0701 International Part # 6040608C91 Replaces Alliant Power Part # AP54850, AP54851 The Denso OEM New pump is brand new, with every piece on the Oct 2, 2019 · Do you own an LML with the dreaded CP4 Injection Pump? There's a lot of misinformation floating around the internet about the LML CP4. Diesel Power Products is your diesel performance headquarters proudly located in Spokane Valley, Washington. Outside of the major items covered below, the L5P also received: a strengthened cylinder block, improved glow plugs, a new camshaft design, a high capacity engine oil cooler, an upgraded EGR system, and a stronger transmission w Jul 20, 2022 · Fuel Pump,having to do a whole fuel rail system with new injectors,started out missing throwing #5 injector code,got worse from there ,pulled fuel filter found metal shavings. 6L LML or LGH. GM engineers got involved and blamed the super dry diesel from California at the time wasn't lubricating the pump. May 27, 2025 · But why is the CP4 pump such a problem child? And what can be done to protect your investment? The answers involve fuel quality, internal design shortcomings, and smart upgrades – both mechanical and chemical. May 25, 2023 · The L5P has made great reliability improvements and is, in my opinion, the most reliable diesel engine being produced today. Therefore, both pumps, rails, injectors and injector lines were replaced. Despite the same 6. . 6-liter L5P V-8 Duramax Turbo Diesel Engine that General Motors launched in 2017 and will tell you about injector problems it may face. Jul 25, 2024 · Find out the most common L5P Duramax problems, including emissions issues and fuel system failures, and learn how to fix or prevent them. Jan 26, 2026 · The Denso HP4 high-pressure fuel pump used in the L5P represents a major upgrade from the problematic Bosch injection pump found in the previous LML series. Needs everything flushed . Mar 5, 2026 · In fact, the Bosch CP3 high-pressure injection pump has proven to be one of the most reliable diesel fuel systems of all time. Oct 6, 2020 · Lots of posts other places about connector issues being the real problem rather than the injectors. Of course install a new injector and there is a fresh electrical connection. From injector failures to overheating, L5P Duramax Problems can be solved with our expert maintenance and repair recommendations. Our online storefront provides the most comprehensive catalog for your diesel truck and we offer the industry's best product support for your Dodge Ram Cummins, Ford Powerstroke, GM Duramax, Ram EcoDiesel, Nissan Titan XD, Volkswagen TDi, or Sprinter. Mar 11, 2025 · Explore Duramax engine problems by year, from LB7 injector failures to LML CP4 pump issues, plus tips and upgrades to prevent common reliability concerns. Apr 6, 2025 · The truck had 3 months of powertrain left and the dealer diag'd the HP4 pump was eating itself. However, it does suffer a few common problems such as MAP sensor failure, a weak transmission, and fuel injector failure. This improvement has substantially reduced fuel system failures and enhanced overall power reliability. Common complaints included the water pump failing, fuel injector imbalance, and turbo lag under load. Could it be the best GM diesel engine? He will cover updates seen in the L5P from the LML engine, common problems, and reliability for the Duramax L5P engine. Follow these steps and you'll be able to save thousands of dollars in potential damage to your 6. Sep 1, 2021 · The Bosch CP4 pump is a high-pressure fuel pump, or injection pump, that debuted in 2011 in the Ford Powerstroke and GM Duramax engines. jaust dlvrv aqrqdy lzjn seqksy tzqs qjigss vvhqmn gnmnu liqjs