07 Rainier runs cool........maybe

[russ455]

Just purchased a 2007 Rainier and have a question. heater works and blows warm/hot air. But, Temp gauge barely moves. scan tool shows coolant temp climbs to about 100 but no higher. Lower radiator hose never gets hot. Just warm. Upper hose does get hot

I replaced the thermostat and same problem. Tested the old thermostat and it seems to stay closed until about 200 degrees..

Maybe an ECTsensor? Looks to be at the back of the motor on the passenger side so not easy to reach. Ikeep getting the P0128 code so there is an issue somewhere

 

[russ455]

Coolant temp sensor fixed the problem................PITA to find at the rear of the motor

Now a steady 210 degrees

 

[Wooluf1952]

Welcome

In case you haven't heard:
http://gmtnation.com/f5/welcome-gmtnation-com-heres-story-226/


Glad you found the fix.