Conditions for Running the DTC

WARNING: This page is about a different car, the 2006 Buick LaCrosse and 2006 Buick Allure. However, it is still accessible from the selected car via links, so may be relevant.

The engine is operating.
The engine speed is between 480-5,000 RPM.
The ignition 1 voltage is between 10.5-18 volts.
DTCs P0351, P0352, P0353, P0354, P0355 and P0356 run continuously once the above conditions are met.