As I was driving in to work tonight, I noticed that my heater was only blowing luke warm air and the coolant gauge never came up at all. It was about a 30 mile drive so there was plenty of time for the engine to warm up, but the gauge still read like it was dead cold.

When I got to work I popped the hood and saw that the overflow was bone dry and the overflow hose that runs from the radiator cap to the overflow tank had come off at the cap. I guess that might explain why i had no heat (or does it?) but why wouldn't the temp gauge be reading cold? Is there something more sinister at work here? I haven't run the truck since then because I can't just take off until my shift is over in the morning.

 

Top off your radiator.

If you have enough air in the system the sensor doesn't get a reading.

 

thermostat could be bad as well as low on coolant. check the antifreeze first.

 

Yep, bad thermostat. It wasn't just stuck, it was snapped almost in two!
"Well there's yer problem!"

 

yeah, my brothers 96 mustang gt did the same thing twice. must just be some bad parts.