JC Car Care and Tire - South
4429 Tumbleweed Drive, Saint Charles, MO 63304 | 636.928.5150

The Missouri push for fuel economy has the benefit of using less gas as well as fewer emissions in our local St Charles environment. Cars and trucks run cleaner than ever.

Many people in the St Charles area may not realize that the first federally mandated pollution control device was in 1960: the PCV valve.

'PCV' stands for Positive Crankcase Ventilation. The crankcase is the lower part of the engine where the crankshaft is housed and where the engine oil lives. When fuel is burned in the engine some of the explosive gases from combustion squeeze past the pistons and down into the crankcase.

Now this gas is about 70 percent unburned fuel. If it were allowed to remain in the crankcase, it would contaminate the oil and quickly turn it to sludge. Sludge is like Vaseline and clogs passages in the engine, leading to damage.

Also, the pressure build-up would blow out seals and gaskets. In the old days, there was just a hose that vented the crankcase out into the air, obviously not good for the environment.

Enter the PCV valve. It's a small, one-way valve that lets out the gases from the crankcase and routes them back into the air intake system where they can be re-burned in the engine.

As you might imagine, the valve gets gummed up over time. If you skip oil changes now and then, the PCV valve gets gummed up even faster. If the PCV valve is sticking you could have oil leaks. Fortunately, the PCV valve is very inexpensive to replace. Some can even be checked for function by your technician.

Manufacturers usually recommend they be changed somewhere between 20 and 50 thousand miles (30,000-80,000 kilometers). Unfortunately, PCV valve replacement is left out of some owner's manuals, so you may need to ask your service advisor.

Come down to JC Car Care and Tire - South and have us take a look at the condition of your PCV valve to ensure you are running at top efficiency. Just come by our service station in St Charles, Missouri 63304, or give us a call at 636-928-5150.