ok i have flushed out core hose with air and water and bled system but what i have found that the coolant is not running steady into the core it is spitting when i bled the system the coolant was come out the pin hole on left hose but when i gave it gas the cooolant stop coming out of the bleeder hole also i get no temp gauge reading no matter how long i run the car gauge work before was saying it was running hot so took mechanic he change the sensor took back now he says gauge im a little wary of that since it worked before sensor and i been going at with him about the heat because it worked before i had timing belt put in water pump thermo now im wondering if the thermostat is stuck open or if water pump faulty he says no claims heater core but since i flushed it out i get heat when i run down the road but not when i idle and the spitting of the coolant leaves to believe somthing not pumping right anyhelp would be appreciated ty tony

 

If you flushed the heater core and it got better then your heater core is clogged (even if you did flush it). You have to take the dash out and the box.