Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2007 Hummer H2 4D Utility PickupFACTORY OEM SERVICE PROCEDURE
Engine Controls And Fuel - 6.0L - Troubleshooting
- Symptoms - Engine Controls
- Hard Start
- Surges/Chuggles
- Lack of Power, Sluggishness, or Sponginess
- Detonation/Spark Knock
- Hesitation, Sag, Stumble
- Cuts Out, Misses
- Poor Fuel Economy
- Poor Fuel Fill Quality
- Rough, Unstable, or Incorrect Idle and Stalling
- Dieseling, Run-On
- Backfire
- Malfunction Indicator Lamp (MIL) Inoperative
- Malfunction Indicator Lamp (MIL) Always On
- Engine Cranks but Does Not Run
- Ignition Relay Diagnosis
- Fuel Pump Electrical Circuit Diagnosis
- Fuel System Diagnosis
- Fuel Injector Solenoid Coil Test
- Fuel Injector Balance Test with Special Tool
- Fuel Injector Balance Test with Tech 2
- Fuel Tank Leak Test
- Alcohol/Contaminants-in-Fuel Diagnosis (without Special Tool and without E85)
- Alcohol/Contaminants-in-Fuel Diagnosis (with Special Tool)
- Electronic Ignition (EI) System Diagnosis
- Inspection/Maintenance (I/M) System Check
- Inspection/Maintenance (I/M) Complete System Set Procedure
- Inspection/Maintenance (I/M) System DTC Table
- Service Bay Test
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.
