Last winter, my heater started just blowing cool-cold air. I replaced the heater core at the beginning of January this year, heat worked for about a week and now it's started blowing cool-cold air again. Today, I have no idea if it is related in any way but I can hear liquid sloshing around when I accelerate. I don't smell anything sweet and the floors arent wet at all.... Please help! Id rather not take it to a shop if I don't have to.
If you determine that your thermostat is stuck there is a video on utube View: https://youtu.be/taH8wTVD3vU that shows how to replace.if you are adventurous enough to take it on.
There are a few things that come to mind. I have seen situations where an air pocket can form in the heater core, since it is generally one of the higher points of elevation compared to the rest of the cooling system. It is vital to make sure that there is no air in your cooling system. Most shops use a vacuum system to draw a perfect vacuum on the cooling system, and use that vacuum to draw in the coolant. That significantly reduces the risk of an air pocket forming in the system. You can fill the coolant system yourself without any tools, but it takes a little bit of work. There are generally speaking at least one but as many as 3-4 vent points throughout the cooling system. You have to open each vent to bleed out the air as you fill the system with coolant, shutting each vent once all air is expelled. Then, you start the engine, and continue filling the coolant system until it does not accept any more coolant. Allow the engine to run, but monitor the engine coolant temperature closely. If it begins to go above normal operating temperature, you must shut off the engine before the engine overheats. Then, you allow it to cool and vent/fill the system again. Continue this process until all air is out of the system, and you'll probably be good to go. Another common issue, is that sludge and stuff can plug the heater hoses running to the heater core. This isn't a difficult or expensive issue to fix. I generally recommend flushing the cooling system at least once every 5-6 years. It can be done on your own, with just a garden hose. You essentially remove the hose clamps and hoses to the radiator as well as the heater core, and flush water in both directions through each. You continue until the water that exits is clear and clean. If you'd like, PM me and I'll send you some more specific instructions on how to do this. If you hire a shop to do this work for you, it's generally not too expensive. Down here in the US, it's generally a $150-$200 total including new coolant. These are the more generic fixes for this issue. If it is an issue with the thermostat, you can generally tell since the engine coolant temperature gauge will not cycle to normal operating temperature while driving. If you are hearing sloshing sounds in the heater core, that generally is an indication that there is air. I would say that I am about 90% sure that your issue is just an air pocket which has collected in the heater core. ~Will Courtier~
I've never done a heater core on a Nitro, but on a Durango they're a pain in the fucking ass, the entire dash has to come out. This is months old, so what happened? Like it has been said, if you're low on coolant OR you have a lot of air in your cooling system, it'll blow cold.
