hey guys got a 01 blazer here bought last year had tons of heat. now im getting less heat than last year when driving ,noticed at stop light and idling still for about one min it starts to blow a tad cooler now. Fluid is up both heater core hoses warm and top radiator hose is warm and lower is cold should it be? plus the temp gauge is were it usually sits when it runs hot . anyone got any ideas before i head to garage? Thanks

If it is full then the problem is most likely the thermostat.

Auto or manual heater controls?
Does all vents and tempt controls switch back and forth?
Engine up to 195 degrees?

If so all hoses should be hot to touch.
Is both heater hoses hot to touch?

both heater core hoses get hot and so does top radiator hose the lower radiator hose is not getting hot its cool ----- fluid in radiator is full manual controls for heat..... any help ? thanks again

both heater core hoses get hot and so does top radiator hose the lower radiator hose is not getting hot its cool ----- fluid in radiator is full manual controls for heat..... any help ? thanks again

Is engine up to 195 degrees?

yes it goes up to 195 havent seen anything strange with the temp

Does the temp control switch /go to cold and warm and hot?

Pull heater hoses and check for good coolant flow to and threw heater core.
Try a back flush on heater core.

Has coolant ever been serviced?

Check actuater motor and shaft for full travel from cold to hot.

Up in the how to section there is some good info and pictures of the actuator motor.

ok will do thanks for the help greatly appreciated

How to is in S-10 forum.
http://www.automotiveforums.com/vbulletin/forumdisplay.php?f=2069

Let us know what you find.
Good luck

had radiator flushed and heater core hoses flushed and blown out seems to have it fixed now. was way cheaper than trying a new heater core. anyone should try this flush and blown out on hoses and heater core before buying .

had radiator flushed and heater core hoses flushed and blown out seems to have it fixed now. was way cheaper than trying a new heater core. anyone should try this flush and blown out on hoses and heater core before buying .


Thanks for posting back how it went.

Also a good coolant service ever 3 years or 50K heads off a lot of problems.