Why Your Car Is Leaking Oil When Parked
If you’ve backed out of your parking space and noticed the telltale black stain on the ground, your heart can sink a bit. Having a car leaking oil when parked isn’t the end of the world, though. There are several reasons why your car might be leaking oil, and while some of them are serious, others can be fixed fairly quickly.
The most common cause of oil leaks is a leaking oil pan. The oil pan sits under your engine and catches the oil that drips out when the vehicle is not in use. It’s usually an irregularly shaped piece of metal that covers the engine compartment from below and attaches to the frame with several bolts. There should be a valve set into the lowest point on the pan that’s opened to drain oil during an auto service appointment. If the pan in your car is cracked or punctured, usually from some road debris, your car can slowly leak oil when you park and the fluid begins to pool in the pan.
Leaking oil can also be caused by degraded engine gaskets. When the motor is running, the oil pump circulates oil around the engine parts to keep them lubricated and running well. The engine gaskets sit at various places around the engine and keep the oil inside the machinery. When these go bad, which can be caused by changes in the weather or exposure to road debris, oil can leak out over the rest of the engine and onto the ground.
In a similar way, you might have degraded or broken oil seals. Oil gets pumped around the engine inside a system of tubes that end with rubberized seals. These should be soft and flexible, so the seal forms a good barrier around connection points. The weather in Belleville, Illinois, however, swings from snow and ice to warm and muggy, which over time causes the seals to stiffen and crack, leaking oil as they go.