Conditions For Setting DTC
WARNING: This page is about a different car, the 2002 Pontiac Aztek and 2002 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.
If the PCM detects a temperature difference between the ECT sensor and the IAT sensor of more than 27°F (15°C), the vehicle must be driven for 5 minutes over 15 MPH. If the IAT sensor temperature decreases more than 12.6°F (7°C), a block heater is detected and the test is aborted. If the IAT sensor temperature does not decrease, a block heater was not detected and DTC P0116 sets; or the temperature difference between the ECT and the IAT at start up is greater than 252°F (140°C), and the time spent cranking the engine, without starting, is greater than 10 seconds.