Does the car give some clue when it shifts from Open Loop to Closed Loop? That is, some way the driver could definitively tell when that happens? On our old Protege5 I could tell by a change in the idle, but that only works if the car is sitting still, it would be nice to have this information when the car is moving. Failing that, any idea which of the huge number of displays available in Torque Pro (with the Prius PIDs added) will show this? I'm curious because the car seems to be slow to warm up, as judged solely by the change in MPG on the bar display. Might or might not be correlated with the OL to CL transition. Seems like it should be.
Generic OBD2 data should have a PID such as "loop status" (OL or CL, open or closed, etc). Or look to see when STFT starts moving around. As far as actually "warming up", you can monitor ECT (engine coolant temperature) to see if the thermostat is working correctly. Most failures I see are the stat opening early. If it gets real bad then the ECM should set P0128, but that's "should". You can check ECT on an extended 50-60mph cruise (ICE running continuously)on a cold day (turn heater off) - ECT should stay around 180°F. Airflow should remove heat faster than the ICE can supply it. Or start the (cold) engine and monitor ECT while keeping throttle applied in park so that ICE stays running. ECT should fluctuate after CHS operation then climb steadily, before "leveling off" around 180°F. Once the radiator is fully "hot", then ECT will go up again. Before the stat opens, the radiator core should stay cold. Posted via the PriusChat mobile app.
