Your engine oil is as essential to your car as your blood is to your body. Without it, your motor won’t run. And just like a doctor can tell a lot about your health by testing your blood, you can ...

CARS.COM — We’ll pull no punches in saying it: Engine oil is a crucial thing to keep tabs on from a maintenance perspective. That means you should check your vehicle’s engine oil at least once a month ...

At a time when vehicle diagnostics can demand a computer science degree, being able to get some insight into your engine health with nothing but a rag and a bit of know-how can be downright refreshing ...

Got a low-oil warning light? It's bad to have too little oil in your engine, but it's also a problem if you add too much. So be careful not to overfill your engine. Also consult your owner's manual to ...

Contaminants can tell you if you have any engine coolant leaking into the cylinders, and how well your engine air filter and oil filters are working. Second, you want to check your oil’s health, to ...