Diagnostic Aids

WARNING: This page is about a different car, the 2019 Buick Cascada, 2018 Buick Cascada, and 2017 Buick Cascada. However, it is still accessible from the selected car via links, so may be relevant.

Verify the following conditions do not exist:

Accessory drive bracket - Defective/Loose/Visible Damage
Belt Driven Device - Defective/Loose/Visible Damage
Brake Rotor - Excessive runout
Drive Belt - Defective/Loose/Visible Damage
Drive Shaft - Excessive runout
During certain road conditions:Rough
Tire and wheel assemblies which exhibit excessive runout can produce vibrations even if the assemblies are balanced.
Incorrect operation of the component: Transmission
Command the Cylinder Deactivation system On with a scan tool, then observe the misfire counters when commanding the system Off. If the misfire counters are incrementing, inspect for a sticking valve lifter. - If equipped
High resistance in the circuits of the component may set DTC P0300 - P0304 without setting the DTC for the component:Q17 Fuel Injector
If the condition is intermittent, wiggle the related wiring harnesses and connectors, with the ignition/vehicle on or engine running, while monitoring the scan tool circuit status parameters for the component. The parameters will display if there is a condition with the circuit or a connection.
DTC P0300 may set when there is a condition with the component circuits: B52 Heated Oxygen Sensor