My car needs a new coolant temp sensor. Do I have to drain some coolant out and then put it in or what. I don't want coolant all over my driveway. What should I do? Thanks!

 

The one in the water pump or the one for the temp gauge in the driver side head? The sensor in the water pump is easy. Teflon tape the threads on the new sensor, throw a couple cloth towels under your car, unscrew the old sensor and quickly put the new one in. Takes 2 hands, one to unscrew the old sensor and the other to place the new one in. I did it this way and lost less than 8oz fluid. Gotta be quick though.

 

The one in the head.

 

your gonna have to drain most of the coolant out to change that. After the coolant's out its easy

 

Just put a catch pan under it, it isn't going to spill out that much coolant from the head. After you replace it, just put the coolant back in and call it a day.