Diagnostic Aids
WARNING: This page is about a different car, the 2017 Chevrolet Suburban 3500 HD. However, it is still accessible from the selected car via links, so may be relevant.
- Ensure that each fuel injector is connected to the proper fuel injector harness connector. Refer to Engine Controls Schematics
- A high resistance condition on any fuel injector control circuit can cause an engine misfire P0300 - P0308 DTC to set without setting a fuel injector circuit P0201 - P0208 DTC.
- A high resistance condition on any ignition control (IC) circuit can cause an engine misfire P0300 - P0308 DTC to set without setting an IC circuit P0351 - P0358 DTC.
- A misfire may only occur when the engine is operating under a load or when the engine is cold.
- A misfire DTC could be caused by an excessive vibration from sources other than the engine. Inspect the following for possible sources of vibration:
- A tire or wheel that is out of round or balance
- Variable thickness brake rotors
- An unbalanced drive shaft
- Certain rough road conditions
- Transmission operation
- A damaged accessory drive component or belt; remove the belt and safely operate the engine to evaluate
- A damaged reluctor wheel