it's normal on the streets. so whenever i drive faster the temp drops down even if I have been driving long time. i also used to get around 340 a tank, now about 275. i changed the ported vacuum switch. i'm also wondering if the thermostat has any effect on the pvs. thanks
My car over cools on the freeway. I think it's a faulty thermostat. would this also cause poor gas mileage?
Yes a faulty thermostat will definitely cause the symptoms that you described. In fact that is the only thing that can cause it. And, yes it will also cause you to get less MPG because your car runs richer when the engine is colder.The thermostat wouldn't have any direct influence on the PVS, because all the thermostat does is direct the engine coolant to either recirculate in the engine or go through the radiator. When the thermostat is stuck open all of hte coolant will go through the radiator and thus cool the engine excessively under conditions of high air flow through the radiator, this in turn will cause a lower temperature of the engine might affect the PVS.
My car over cools on the freeway. I think it's a faulty thermostat. would this also cause poor gas mileage?
Yes, over cooling can cause a decrease in mileage. Modern cars are designed to run within certain ranges, when the motor is too cool the computer thinks it's in a warm up mode and enriches the fuel mixture-which leads to lower fuel mil age.
