An engine that’s “underheating” could be a sign that your thermostat is on the blink.
The last few times you drove your car or truck during cold weather you noticed that your heater didn’t seem to be working really well. But, hey, that’s to be expected when a vehicle gets older and, anyway, winter was almost over. So nothing to worry about now, right? Not necessarily. That lack of heat could indicate that your thermostat is stuck in the open, or partly open, position.
The thermostat’s job is to keep the engine working at the proper temperature. It closes or opens to either block coolant from reaching the engine before it’s reached the proper temperature or to let the coolant in to keep the engine from overheating. Now, most drivers know that it’s a bad thing if their vehicle overheats because that can cause significant engine damage. But it’s also not a good thing if your car or truck “underheats” (quite aside from causing you to freeze while driving).
Tom Magliozzi from the PBS TV show Car Talk (cartalk.com) explains, while noting that, in the old days, some mechanics solved an overheating problem by removing the thermostat: “Most cars now have computers, which constantly monitor the engine temperature and adjust things accordingly. If the computer thinks the engine is cold – and it WILL be cold without a thermostat – it’ll richen the fuel mixture. That will lead to poor mileage, carbon buildup, and eventually, [an expensive] repair bill for a new catalytic converter.”
So, if your car or truck heater isn’t warming things up; or, on the other hand, if things are too hot with steam coming from under the hood or your temperature gauge heading for the red zone, you need to bring your vehicle into Terry’s Car Care in Madison. We’ll check that thermostat and get your vehicle all fixed up so you don’t miss the Moth Watch at Devil’s Lake State Park in Baraboo.