how do i know if my heater core is not working? my motor isntin the car so i cant turn it on and see. is there a way i can see if it works without the motor in the car.
It would have to be under pressure to test it. I am not sure if there is a way. btw why do you ask. Were you having problems before the engine came out.
How many miles are on the car? This will be the only way to judge / guess if it's time to tear out the dash for the core. When was the core replaced last (if you know.)
FWIW a heater core goes out about every 60,000 miles from abuse and poor design by Ford.
If the heater core lets go, it usually burst's and then hot coolant spews all over the passenger foot well (Messy / Yucky / Smelly pretty much sums that up)
The thermostat controls how fast the heater core warms up... But a Heater core can plug (not too often)
If you have heating problems, it could be the thermostat, the door not closing, air inside the coolant and possibly a plugged heater core