bypass thermostat

[david944]

Something had me thinking. Can you leave the thermostat out and just not have one in there? How would the car be say on a 15 degree morning.

[wolfrpi]

I believe that the car would take longer to heat up because the coolant would be circulating through the radiator instead of just staying in the engine block. Further, removing the thermostat will likely increase your emissions and increase your fuel consumption as the DME that controls the engine is programmed to run the motor with the thermostat in place. Additionally, all internal combustion engines run more efficiently the hotter they get (in terms of fuel consumption).

Erick

[Lawrence Coppari]

The thermostat is stuck open on my turbo 944. In cold weather you lose your heat when the car is in motion. Highway speeds and 20 F gives no heat. Plus, gas mileage has dropped off.

[jwn]

My thermostat was stuck wide open last winter. On highways in Chicago at 0 to 20 degrees the temperature rarely lifted up at all, and occasionally, it would get so cold that the MPG gauge would drop to just about nothing while the DME screwed around with the mixture.

I would recommend not running without one (although I did get between 24 to 28 mpg and managed to pass my emissions test without it working right). The new thermostat is much more predictable as the needle, rather than being all over the gauge, pretty much stays in one spot.

[divezic]

Furthermore, your engine longevity is directly related to the oil temp. If you look at a graph of oil temp vs engine life, the peak (longest life) is at a specific temperature for each type of engine. The further you run your engine away from the ideal oil temp, it's ware life exponentially decreases.

The "benefits" of not putting in a properly working thermostat are nowhere near the amount of problems caused by continuously running a cold engine.

------------------
Dave
1984 944
Stuck in hell with a year to go.