LEMON Manuals: Even more car manuals for everyone
Home >> Hummer >> 2008 >> H2 4D Utility Wagon >> Repair and Diagnosis >> External Pages >> Different car >> Section 365 (Engine Controls And Fuel - Hybrid (LZ1) - DTC P0351 Through DTC P3449 And Troubleshooting) >> Diagnostic Information and Procedures >> DTC P1400 >> Circuit/System Testing

Circuit/System Testing

WARNING: This page is about a different car, the 2011 GMC Yukon, 2011 Chevrolet Tahoe, and 2011 Cadillac Escalade. However, it is still accessible from the selected car via links, so may be relevant.
  1. Inspect the air intake system for the following:
    • Damage, restriction, or modification
    • Dirty or deteriorating air filter element
    • Crankcase ventilation system for correct operation-Refer to Crankcase Ventilation System Inspection/Diagnosis .
    • Water intrusion
    • Vacuum leak and other un-metered air downstream of the mass air flow (MAF) sensor
    • Intake manifold leak
  2. Inspect the exhaust system for the following:
  3. Inspect the engine mechanical for items that could alter the air flow into the combustion chamber. Refer to Symptoms - Engine Mechanical .