TCH Oil Temperature

[Old-Crows]

I've read somewhere, perhaps on this Forum, that the ICE's oil temperature controls its operation. I'm trying to figure out how that would work as it takes a long time to get the oil up to 'operating' temperature and that would mean the ICE would operate more than necessary to charge batteries and provide hot coolant for the heater.

Any thoughts, Gents?

OBTW, I checked the OT on an 80+ day after a long run and the OT measured about 133F. Well below the thermostat opening temperature. (Let me explain.... I use an infrared hand held thermometer to measure the temp. After shutting down the car, I quickly check the OT by measuring the temperature oil on the of the end of the dip stick. Sounds wacky but its close enough for 'gummin't work.' For example, my '04 Sienna after its been cookin' runs about 190-220F depending on the ambient. Which is about what it should be .... approximately the same temp as the coolant temp.)

[tharvey]

To the best of my knowledge it has always been the coolant temperature in the engine and not the coolant in the rad or the oil that is used for determining the on and off for the ice.

If you think about it, we can change the type and weight of oil which would mean everyone would have different vehicle characteristics.

Also if your vehicle was sitting in the sun, the rad coolant could exceed operating limits and throw off the engine completely.

Generally all vehicles I have worked on, get the temperature from the actual engine operating temperature which is determined by the fluid in the actual engine.

Another thing to consider would be the engine heater is used to heat the engine block and not the oil or radiator coolant temperature.

I am pretty sure about this, someone could chirp in if I am wrong.

Tim

[GeorgiaHybrid]

The ICE on or off is determined by the temp in the O2 sensors. The catalytic convertor must be up to temp to work correctly. If the convertor starts to cool off, the ICE will fire up and increase the temp in the convertor. They are required to do this in order to maintain the EPA ratings on the car.

The engine coolant or oil temp can still be high but the engine will not shut off due to the temp in the exhaust system.

[ekpolk]

Originally Posted by GeorgiaHybrid

The ICE on or off is determined by the temp in the O2 sensors. The catalytic convertor must be up to temp to work correctly. If the convertor starts to cool off, the ICE will fire up and increase the temp in the convertor. They are required to do this in order to maintain the EPA ratings on the car.

The engine coolant or oil temp can still be high but the engine will not shut off due to the temp in the exhaust system.

Yup, that's correct as far as I know. Unfortunately, I don't know the ScanGauge-XGauge codes necessary to get a readout of that parameter. Anyone broken that code yet?

[GeorgiaHybrid]

Gene,

I wish I knew the codes. We might have to export a TCH to India or China and have them find the codes for us. They seem to be able to hack any other software over there, why not the TCH....