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PCV Valve Service at Commerce Auto Repair in Commerce

February 8, 2020

Today, we are talking about your PCV valve. Unburnt fuel is forced into the crankcase as your engine runs.  The PCV (positive crankcase ventilation) valve vents this unburnt fuel and oil vapors from the crankcase and sends it back into the air intake system to be burned in the engine.  A clogged PCV will not allow these vapors to escape. This can dilute and contaminate the oil, leading to damaging engine oil sludge. It can also cause vehicle engine corrosion, something we see occasionally at Commerce Auto Repair. At high speeds on Michigan freeways, the pressure can build up to the point that gaskets and seals start to leak.

Back in the old days, vehicles were simply installed with 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 vehicle's engine.

This is much better for air quality and improves fuel economy also. (Budget-conscious Commerce drivers take note!) The little valve that performs this important function is the PCV valve. 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 at Commerce Auto Repair in Commerce and quick and inexpensive to replace. Even so, it's often overlooked because many Commerce vehicle owners don't know about it. Check your vehicle owner's manual or ask your Commerce Auto Repair service advisor. 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. Now some vehicles have a small separate air filter for the breather tube called the breather element. That'll need to be replaced at Commerce Auto Repair when it gets dirty.

Please ask your Commerce service advisor about your PCV valve. For the price of a couple of burger combo meals in Commerce, you can avoid some very engine repairs.

Commerce Auto Repair
9575 Commerce Rd.
Commerce, Michigan 48382
248.363.3749

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