What Causes Injection Pumps To Fail?

There may be many reasons for injection pumps to fail.

Before we answer the question, ‘What causes injection pumps to fail?,’ we need to define what they are. Injection pumps are mechanical devices specific to engines using diesel fuel. These devices make diesel fuel available for the internal combustion process and are typically powered by the indirect connection to a crankshaft via gears, chains or timing belt. This indirect connection also may drive the camshaft.

As indicated by Under Hood Service, poor maintenance is the top destroyer of this critical diesel engine part.  The chief duty of any owner wanting to maintain his vehicle investment is to get regular oil changes. Lack of lubricant between the camshaft lobes and the pump prevents the pistons from moving at a rate significant enough to generate the kind of pressure needed.

As part of this vital step, an owner of a diesel fuel-based vehicle must ensure the proper oil is used during oil changes. The oil must meet the specifications of the original equipment manufacturer (OEM). In addition, the tank must always be filled with diesel fuel.

While most owners would see this as a ‘no-brainer’, many have been blindsided by the fact that diesel fuel in the U.S. has a much lower sulfur content than that which is available in European markets. Nevertheless, the Bosch CP4 fuel injection pump is failing because it is made in Europe and needs diesel with a higher sulfur content to operate optimally.

According to Under Hood Service, the hydraulic pistons of this model struggle to continue to work and deliver adequate fuel to the engine. Without the pistons working at top efficiency, the pressure is lowered and fuel delivery is compromised.

Another reason an injector pump may fail is because of leaks. This device operates at high pressure, giving rise to fuel leakage. These can occur in a resting state as well and may require a factory scan tool to identify.

What Type of Diesel Fuel Pump is the Bosch CP4?

The CP4 diesel fuel pump is a common rail fuel injection pump. Controlled electronically, this system was created to meet the environmental demands of the new millennium in terms of exhaust control. As indicated by Fassride.com, it is made up of a supply pump, common rail, injectors run electronically, engine sensors, and an overarching computer system controlling the whole system.

What Vehicles Are Affected By Problems with the Bosch CP4?

The issue at the heart of the problems with the Bosch CP4 is that diesel fuel-based manufacturers in the U.S. were supposed to know that this European model fuel injector would not work well using low-sulfur diesel fuel. General Motors (GM) and Chevrolet trucks using a Duramax 6.6L V8 or LGH engine manufactured between 2010 and 2016 are at risk of this issue.

Join a Free GM Fuel Pump Class Action Lawsuit Investigation

You may be eligible to join this GM fuel pump class action lawsuit investigation if you bought one of these GM vehicles:

• 2011-2016 Chevrolet Silverado 2500HD (6.6L V8 Duramax LML engine)
• 2011-2016 Chevrolet Silverado 3500HD (6.6L V8 Duramax LML)
• 2011-2016 GMC Sierra 2500HD (6.6L V8 Duramax LML)
• 2011-2016 GMC Sierra 3500HD (6.6L V8 Duramax Diesel Trucks LML)
• 2010-2011 Chevrolet Express (6.6L Duramax LGH engine)
• 2010-2011 GMC Savana (6.6L Duramax LGH engine)
• 2010-2011 GMC Sierra Chassis Cabs/Pickup Box Delete (6.6L Duramax LGH engine)
• 2011-2012 Chevrolet Silverado 2500HD and 3500 (6.6L V8 Duramax LGH engine)
• 2011-2012 GMC Sierra 2500HD and 3500 (6.6L V8 Duramax LGH engine)

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