Conditions for Running the DTC

WARNING: This page is about a different car, the 2004 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.

The engine is operating for more than 3 seconds.
The fuel level is between 12-88 percent.
The start up engine coolant temperature (ECT) is less than 36° C (97° F).
The vehicle speed is less than 31 km/h (19 mph).
The ECM is commanding purge.
The ratio between ambient pressure and the calculated manifold pressure is less than 0.6.