Help.
I've recently had my alternator replaced (new) and began noticing that my cars temperature drops significatly when driving on the highway at 55+ MPH. I notice this only happening when driving on the highway and when driving on the street (20-30 MPH) the engines temparature runs normal...btw, it's Winter here in Illinois.
I once stopped the car when the temperature droped and checked the coolant hose - didnt feel hot at all compared to when the car runs on the streets.
Since noticing this problem I've had the following replaced; new radiator, new thermostat, new inginition cable.
Car startup warmup is fine, take about 3-5 minutes to fully warm up.
Again car runs hot and heater works fine only when driving on streets.
Car year: 99
Mileage: 111000
Thank you.