Posted by & filed under Engine.

Today, we are talking about your PCV valve. The PCV Valve is a little, inexpensive part that does a big job for your car. PCV stands for Positive Crankcase Ventilation.

The crankcase is the bottom area of the engine that holds the oil. When the SUV engine’s running, fuel is burned to generate power. Most of the exhaust from combustion goes out through the exhaust system. But some exhaust blows by the pistons and goes into the lower engine, or crankcase.

pcv valve


These hot gases are about seventy percent unburned fuel. This can dilute and contaminate the oil, leading to damaging engine oil sludge. It can also cause SUV engine corrosion, something we see occasionally at Central Avenue Automotive. At high speeds on Washington freeways, the pressure can build up to the point that gaskets and seals start to leak.

Back in the old days, car makers simply installed a hose that vented these gases out into the atmosphere. But starting in the 1964 model year, environmental protection laws required that these gases be recycled back into the air intake system to be mixed with fuel and burned in the car or SUV’s engine.

This is much better for air quality and improves fuel economy, as well (budget-conscious drivers take note!). The PCV valve lets gases out of the engine, but won’t let anything back in. Over time, the vented gases will gum up the PCV valve and it won’t work well. That can lead to all of the problems I’ve already described, oil leaks, excessive oil consumption, and decreased fuel economy.

Fortunately, it’s very easy to test the PCV Valve and  it’s quick and inexpensive to replace. Even so, it’s often overlooked because many Kent drivers don’t know about it. Check your SUV owner’s manual or ask your Central Avenue Automotive service adviser. If this is the first time you’ve heard of a PCV valve, you might be in line for a replacement.

There’s another aspect to the PCV system. In order for the valve to work correctly, it needs a little clean air to come in. This is done through a breather tube that gets some filtered air from the engine air filter. Some vehicles have a small separate air filter for the breather tube called the breather element. That’ll need to be replaced at Central Avenue Automotive when it gets dirty.

Please ask your considerate Kent service adviser about your PCV valve. For the price of a couple of burger combo meals, you can avoid some very pricey engine repairs.