My Honda has 350,000 plus miles on it. Im origonal owner and the miles are mainly high way long distance to work.Do to the car overheating I replaced the waterpump and thermastat this weekend.The temp is still slowly rising and getting hot. As the temp rises my heater gets cooler.I am looking for advice, a clogged radiator , bad sending unit, i dont know ? There are bugs on the outside of the 1st radiator.I see no fluid in the muffler so I believe the engines ok.
Andy

 

Disconnect sending unit harness connector and temp should be dead cold w/ keyswitch turned to ON.

W/ keyswitch OFF, short sending unit connector to ground. BRIEFLY turn keyswitch to ON and temp indication should begin to quickly move towards HOT. Turn keyswitch OFF before indicator goes full scale or you may damage indicator movement.

If both tests are good, the sending unit is likely faulty, but it's still possible your results are real. Sending unit is not expensive, so probably easier to replace sending unit and see if that resolves problem.

Post again your results.

good luck

 

Super, I appreciate the advice andwill let you know how it goes. I will be working on it this Sunday.
Thanks
Andy