Your Corner Wrench: Making the most out of your car’s heating system – Driving

Yes, the season of discontented driving is coming and with it, annual complaints from drivers and passengers seeking more heat. Long gone are the days of automotive yore when techs and DIY-ers swapped out summer engine thermostats for higher temperature-rated winter ones. Now, pretty much every gasoline engine uses a thermostat rated at 195 degrees Fahrenheit, and trying to use a different temp rated unit will likely lead to an engine computer fault code and a check engine light.

Many will try a simple radiator blocker, such as a piece of cardboard jammed in front, to reduce air flow and increase engine temperatures. This can be risky when operating in stop and start traffic, as it can lead to overheating. About the only vehicles that might benefit from this would be diesel trucks, and even then, a proper vinyl winter cover is a much better idea since these usually have adjustable flaps that can air gets through.

But before even using one of these covers, or try out any of the tips and tricks below, make sure the vehicles temp gauge is operating accurately and be prepared to keep a close eye on it during those ultra-slow commutes.

Flushing cooling systems isnt really required with newer vehicles, but theres an easy test to see if your ride might need one. With the engine running at operating temperature and with the climate control set to max heat, check the temperature difference between the inlet and outlet hoses on the cabins heater by touching the rubber portion of each one with your bare hand. It should never be hot enough to burn skin, but if theres a substantial difference, a power flush might help things.

While doing so, rather than cutting into a heater hose to install a flushing tee, look for a spot to disconnect the hose instead adding extra clamps with a cut is just another reason for a leak. As well, household de-scaling agents such as CLR can be helpful in removing any scale in the system.

Dont increase cabin heat by sealing off the HVACs fresh air intake, because this source of fresh air is critical to keep the windshield and other windows from fogging up. In fact, closing the fresh air intake or using recirculation mode is for air-conditioning-season only.

Maybe your ride just needs some warmer clothes. A thick layer of spray-on undercoating below the floor and lower portion of the engine firewall can help reduce more than just road noise. It may increase cabin temps by reducing heat loss, too.

No, not the vehicle speed but the fan speed. Running the fan on its highest setting will actually reduce the air temp, as it doesnt get enough contact time with the fins on the cabins heater core to produce maximum heat. On frosty days, the highest fan speed you should use is one below the maximum setting.

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Your Corner Wrench: Making the most out of your car's heating system - Driving