HI all just serviced my sierra cvh 1.8 new oil and filter and new COOLANT . ENGINE runs well and keeps good temp when driving.THE fan comes on as normal when ticking over for a bit . BUT my problem is i dont have warm air when engine is warm and all the water pipes and heater pipes are really warm. CAN anyone help/advise wat is causing this???
IS THERE A SUMMER /WINTER THERMOSTAT ??? WHAT IS THE WARMEST THERMOSTAT YOU CAN GET FOR THE CVH???
THANKS

 

Heater matrix is blocked although you may have a bit of flow enough to get both pipes warm.

 

HI thanks for quick reply . IS IT A HARD BIG JOB TO SORT HEATER MATIX???

 

Not done one for years but it's a dash out job I would expect.

 

Not good news but thanks gvk for your quick reply and help

 

You could try flushing it through and back flushing it, might fetch some shit out.

 

Sounds like a blocked matrix like GVK said. Other possibility is heater control not working correctly. I can't remember what type of system a Sierra uses.

 

It's not hard to replace a heater rad, only the bottom half of the dash has to come out to do it

 

thanks steppy

 

Had similar issue in my son's old Corsa.
disconnected both end of the heater pipes from the engine, and stuck a hose down one end. Flushed loads of shit out of the matrix, was right as rain after

 

 

Did you find out the problem i have the same with mine car is running 100% but can't get heat at all