Originally Posted by bholmes88
I have searched everywhere and can not find the answer to why my truck is under heating. Even after running around town for a hour it does not pass 160 or so. I changed the thermostat to a 180 and nothing changed. Today I grabbed my temp gun and checked everything. The upper radiator hose heated to 130, the lower hose stayed at 83 and the heater core hoses hit 180. Any suggestions?
If it is taking a long time for the engine to reach temp, that is if you are going by the gauge in the cluster, then it is possible of two things I can think of one is the sending unit is faulty (happens and when they are faulty they usually report a lower then actual temp). The second thing is to keep the heater core valve closed until the vehicle reaches temp, if for instance I have turned my heat on and the vehicle hasn't already been warmed up, then sometimes the engine never reaches temp. So just make sure the valve is closing. The fact that the heater core reaches 180 tells me that is where all the coolant is going and 180, engine is practically warmed up. So check sensor, replace. Check to make sure the water valve is closing and not clogged.