A few weeks ago I put my car in the shop for a few reasons. My defoster and heater only works when I am driving. If I slow down or if Im idiled the heat/defroster starts blowing cool air. I needed a new serpintine belt. Was having the high pitched squeal as well as a fast jingle-bell noise(my 5 yr old sons description:-). Had an oil leak, bad cv joint, and a bad gasket. To top it all off theres a weird gurgling, slurping liquid sound that no one has been able to diagnose for me for 2 years. After a week and $1000 I got my car back with the same fast jingle-bell noise (high pitched squealing is gone), heater/defroster still blowing cold air when idiled and the weird slurping of liquid sound. I would prefer to fix these problems myself but need some guidance on what the problem is. When it comes to my defroster/heater problem; I have checked the heater core but dont believe that is the issue. Any advice will be greatly appreciated. Thank you!
My car has 130000 miles.
My car has an automatic transmission.
Hi there - the lack of heat from your HVAC system could be a couple of things: bad thermostat, heater control valve, or air in the cooling system. If the engine come up to proper temperature and stays there (i.e. center of the temp gauge), the thermostat is fine. If temp on the gauge stays low, the thermostat needs to be replaced. The gurgling sound you are hearing indicates that there is still air in the coolant system, which needs to be bled - hot air in the heater core doesn’t provide heat, only hot coolant will. The cooling system need to be thoroughly bled. Once these are done - if still no heat - check the heater control valve (and heater controls on the dash) to be sure the valve is opening, and allowing hot coolant into the heater core. For help in getting to the problem quickly, I would recommend an inspection of the heater system by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs. The squeal you hear could be a loose serpentine belt, worn idler pulley or alternator bearing, and the "jingle" noise could be a loose belt tensioner.
Have a car question? Get free advice from our top-rated mechanics.
Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing