Cummins Diesel Repair

Cummins Diesel Repair Services

Master Tech Diesel Injection specializes in diagnosis, repair, and reliability upgrades for every generation of the Ram Cummins diesel engine. Below is a complete list of the most common services we perform, organized by truck generation.

1st Generation (1989–1993) – 5.9L 12-Valve

• Killer Dowel Pin (KDP) prevention and repair
• Lift pump diagnosis, replacement, and upgrades
• Fuel injector testing and replacement
• Exhaust manifold repair or replacement
• Turbocharger failure analysis and replacement
• Complete fuel system diagnostics
• Injection pump rebuild and calibration services (in-house). Upgrades available during rebuild, including fuel pin, 3K governor spring, and fuel turn-up.

2nd Generation (1994–2002) – 5.9L 12-Valve & 24-Valve

• Killer Dowel Pin (KDP) prevention and repair
• VP44 injection pump diagnosis and replacement (1998.5–2002)
• P7100 injection pump repairs, complete rebuilds, and upgrades (including 3K/4K governor springs, delivery valves, and modified fuel plates). All pumps are precision balanced in-house on our test stands before installation.
• Lift pump diagnosis, replacement, and upgrades
• Fuel injector testing, replacement, and performance upgrades (in-house extrusion and balancing available)
• Exhaust manifold repair or replacement
• Turbocharger failure analysis, replacement, and upgrades
• Timing cover gasket replacement
• Head gasket replacement with head studs
• Boost leak checks

3rd Generation (2003–2007) – 5.9L Common Rail

• CP3 injection pump replacement and upgrades
• Fuel injector removal, bench testing, and replacement. Performance upgrades available with in-house extrusion and precision balancing on our Bosch test stand.
• Lift pump diagnosis, replacement, and upgrades
• Fuel Control Actuator (FCA) replacement
• Exhaust manifold repair or replacement
• Turbocharger diagnostics, failure analysis, replacement, and upgrades (precision balanced in-house)

3rd Generation (2007.5–2009) – Early 6.7L

• Killer Grid Heater bolt removal and upgraded solutions (including Banks Monster-Ram and Glacier Diesel Performance grid heater relocation kits)
• CP3 injection pump replacement and upgrades
• Fuel injector removal, bench testing, and replacement. Performance upgrades available with in-house extrusion and precision balancing on our Bosch test stand.
• Lift pump diagnosis, replacement, and upgrades
• Fuel Control Actuator (FCA) replacement
• Exhaust manifold repair or replacement
• Turbocharger diagnostics, failure analysis, replacement, and upgrades (precision balanced in-house)
• 6.7L Cummins turbo actuator bench testing, diagnostics, and replacement
• EGR cooler and EGR valve service

4th Generation (2010–2018) – 6.7L Cummins

• VGT turbocharger diagnosis, actuator repair, or replacement
• Killer Grid Heater bolt removal and upgraded solutions (including Banks Monster-Ram and Glacier Diesel Performance grid heater relocation kits)
• EGR cooler and EGR valve service
• DPF cleaning and regen system diagnosis
• DEF / SCR system diagnosis and repair
• NOx sensor replacement
• Exhaust manifold repair or replacement
• Lift pump diagnosis and upgrades
• Complete fuel system diagnostics, in-house bench testing, replacements, and upgrades
• Timing cover gasket replacement
• Heater core replacment

5th Generation (2019–Present) – 6.7L Cummins

• Bosch CP4.2 high-pressure fuel pump diagnosis and replacement
• CP3 conversion (preventive or after failure)
• Complete fuel system contamination cleanup
• Hydraulic roller lifter and camshaft diagnosis
• Flat-tappet conversion kits (2019–2024)
• VGT turbocharger diagnosis, actuator repair, or replacement
• Killer Grid Heater bolt removal and upgraded solutions (including Banks Monster-Ram and Glacier Diesel Performance grid heater relocation kits)
• EGR cooler and EGR valve service
• DPF / DEF / SCR system diagnosis and repair
• NOx sensor replacement
• Exhaust manifold repair or replacement

Additional Cummins Services (All Generations)

• Full computer diagnostics and drivability diagnosis
• Preventive maintenance packages tailored to each generation
• Reliability and performance upgrade packages
• Complete engine replacement when required

Looking for service on a specific year or problem? Contact us for diagnosis and a clear repair plan.

Serving the Treasure Valley

We provide Cummins diesel diagnosis, repair, and reliability upgrades for customers throughout the Treasure Valley, including:

• Boise
• Meridian
• Nampa
• Caldwell
• Kuna