i can't get my formula to heat up! my 2 back up cars both died, so i'm gonna have to drive my baby in the winter. only problem is i can't get any heat out of her in the interior. i waited to get it to normal operating temp, tried the heater setting, defrost, and vent and NO heat, just blows cold air. It gets mighty cold here, so what can i do? whats broken? i figured the heater core is fine seeing there is no leak inside, and the car doesn't overheat (don't wanna jinx that one). Is it the heater core? is it something else? please, help me.

 

Dude........... change the Thermostat in your car to a 180/195 and flush out your radiator, if your fan motor is coming on and blowing air thru the ducts your running way to cool....a 180 stat will give you moderate heat..a 195 stat will bake your legs off........try that before u change out the heater core........good luck

 

Keep it simple. Check the coolant level, if you havent already. A half-empty radiator will be good enough to cool the engine, but your heater won't work properly (I know this, because I just had to add a gallon of antifreeze to mine, the heater stopped working and so I went looking). After checking that, I would suspect a bad thermostat as well, especially if you don't have any leaks in the system.

 

it's a stock replacement stat, which i think is 195 anyways.

 

also, does the dash need to come off to swap heater cores?

 

coolant level is fine. the heat never worked on the car since i bought it, i need it now though usually i just said screw it cause it's warm outside when i usually drive it. And the thermostat is a new replacement as well, did that this past summer.

 

Then definitely go for the thermostat, they're cheap, and do a flush at the same time. Do all the simple stuff before tearing into the heater core.

 

Thermostat is new already???? Flush it all out real good then. Disconnect the hoses going to the engine from the heater core and give it a good flush as well. See if that helps.

 

Could also be flapper valve inside your ductwork that is run by vaccum. If there is a vacuum leak, the door will not engage and allow hot air to enter the system. Pul off the ac/heat controls, make sure all the vacuum hoses are hooked up and not kinked or cracked, I am not sure of the exact location of the flapper door, maybe someone else can fill in the blanks...

 

sounds like a plan. i flushed the coolant system as a whole recently this summer when i replaced the water pump/thermo. i think i'm gonna stick a garden hose onto one of the heater core inlets, maybe that would push some crap out. i was thinking, maybe it's the heater control valve or something?

 

Since you asked about heater core replacement, let me step back and ask this: is the heater core hooked up?

 

yyup it's hooked up

 

don't worry about the flaps, it's the heat your having a problem with, when the flaps are all ****ed the defrost still works. if it's blowing air, the fan still works, narrows it down to either the heater core being bad, heater core being disconnected, or the engine running very very very cold. The latter is pretty unlikely.

Check to make sure the heater core is connected, not sure how mechanically inclined you are, so there should be two hoses comming out of the firewall on the passenger's side right behind the valve cover, one hose should be run to the water pump, the other should be run to the front of the manifold, people unfamiliar with the heater sometimes think the heater core is the ac condensor/heater fan right behind the passenger side fender.

If that fails, it's pretty likely that the heater core is bad, it's under $50 for a new one from autozone/pepboys (like $15-35), just undo the hoses going to it in the engine bay, undo the under dash cover on the passenger side, there's a black box up in there secured with some screws, undo it and the thing pretty much pops out (real simple, there's a complete tutorial in the technical articles section).

You might also try checking the lines going to the heater core to see if there's a blockage in the hose or nipples/fittings.

If that doesn't fix it....i've got no idea.