I've no heat in my car, i changed thermostat, rad cap, and radiator, flush and bleed the system still no heat, but no it becomes worst i've engine overheat and the fun start working even with -30 out side.

sound like the impelled in your water pump may have failed. Or your system is air bound. Try to open the rad cap when its cold and let it run and see if air bubbles come to the top

How did you check thermostat? Did you check coolant level. Is the auxiliary water pump leakinh

Many people overlook the cooling system pressure cap cheap to replace but often overlooked , the radiator may also be internally restricted. Rad shop would be able to confirm if this is the case. rad cleanout and engine block flush may help. Hopefully this is useful to you.

Possible trapped in system. Bleed system, should have two small screw bleeders, one in front of left valve cover on pipe behind water pump and the other on coolant pipe outlet as you follow upper rad. hose towards engine. Engine cool, remove rad cap, open both bleed screws and fill rad until coolant flows free out both bleed ports. close both bleed screws, rad cap off, start engine and let idle until upper hose is hot to touch , shut off, let it cool down for 20 minutes, top up rad and install cap. restart car ,drive and check.

there should be no air in the cooling system and the system can be bled by using a pressurising equipment . Ensure that the thermostat is placed in the motor the right way with the body facing the hot water (head or block). Air defeats the purpose of having a pressurised cap and system.

Coolant system have bleed points. There is air in your system that needs to be purged out through the purge valves.. There maybe a few. You have to slightly open them when you first fill the system and let the coolant circulate till a little bit of coolant comes from bleed valves then you close them. Letting the system purge air by leaving the radiator cap open is not enough. Are you sure you put the correct temperature thermostat in , and facing the correct way?

After changing the thermostat, did you fill it with 50/50 antifreeze to water?

Is the radiator cap (not actually on the radiator) in good shape and seating properly?

If the answer is yes to all of the this, than I would try picking up some heavy duty flush from the local parts store and flush the system really well.

Hope this helps.

if you have changed the thermostat. did you bleed air out of system, if air is trapped in system it will not heat right! drain radiator and flush it good, but when refilling turn heater on high heat. then bleed air out when refilling system. most all cars have a bleeder for air. if in doubt, call any auto parts store to find out where yours is. if air is in system you will see bubbles appear from bleeder. also when flushing engine, make sure you start vehicle so it circulates through engine as well as refilling system. if the upper radiator hose gets hot then check for heat from car if it is ok! close bleeder and make sure radiator is full. I think the biggest culprit is air trapped in system. before starting the flush, be sure its not caused by low coolant in radiator. have a good day!!

Flush rad & change coolant & thermostat. Check operation of rad fan, & make sure it is coming on when engine reaches normal operating temperature. Be sure to bleed air out good when refilling rad/cooling system. Start engine & turn heater on when refilling & let rad fan come on & off at least 2 or 3 times before putting cap back on rad, and refill rad as needed as you do this. then fill return bottle to proper level & see what happens.

Pretty common on those. I used CLR and disconnected my heater hoses & with a small pump, I ran CLR only, through the heater core, and let it sit in there overnight, flushed it through again next day, back flush as well. re-connect hoses, run engine with heater on, and rad cap off until the rad fan comes on 2 or 3 times, then put cap back on, to bleed air out of system. Cleaned it out enough to get the heat flowing again. If you changed thermostat and didn't let it run with heat on, and rad cap off for a while as described above, then do that first, just to make sure you haven't just got an air lock in the system.