Back to all

PCV Valve Replacement

July 24, 2022



Hello Royal Oak, let's talk about your often-unnoticed but extremely important PCV valve. The energy from exploding fuel is what powers your engine. But some of the vapors from the explosions escape into the lower part of the engine, called the crankcase. The crankcase is where your engine oil hangs out. These gases are about 70% unburned fuel. If the gases were allowed to stay in the crankcase, they would quickly contaminate the oil and turn it to sludge. Royal Oak folks know that sludge is one of the biggest enemies of your engine, clogging it up and eventually leading to expensive failures. Also, the pressure buildup would cause seals and gaskets to blow out. Therefore, these gases need to be vented out.

Pre-1963, gasoline engines had a hose that let the  fumes vent out into the air. In 1963, the federal government required gas engines to have a special one-way valve installed to help reduce dangerous emissions. (Can you imagine how polluted our Michigan air would be if every car had been releasing those poisonous fumes for the last 50 years?) Diesel engines are not required to have these valves.

The positive crankcase ventilation (PCV) valve routes crankcase gases through a hose and back into the air intake system where they are re-burned in the engine. Fresh, clean air is brought into the crankcase through a breather tube. It's really a pretty simple system, but it does the job. The re-circulating air removes moisture and combustion waste from the crankcase, preventing sludge. This extends not only the life of your oil but the engine as well. The PCV relieves pressure in the crankcase, preventing  oil leaks.


Eventually, the PCV valve can get gummed up. Then it can't move enough air through the engine to keep it working properly for Royal Oak vehicles. If the PCV valve is sticking enough, you could have oil leaks, excess oil consumption and a fouled intake system. If you experience hesitation,  surging or an oil leak, it may be a sign of PCV valve problems. Your vehicle's owner's manual may give a recommendation for when the PCV valve should be replaced - usually between 20,000 mi/32,000 km and 50,000 mi/80,000 km. Unfortunately, some don't list a recommendation in the manual, so it can be easy to overlook.


Many PCV system problems can be diagnosed by our technicians at TLC Custom Exhaust Brakes & Tires . Fortunately, PCV valve replacement is both quick and inexpensive at TLC Custom Exhaust Brakes & Tires. Proper oil changes will greatly extend the life of the PCV valve. Skipping a few recommended oil changes can allow varnish and gum to build up in the valve, reducing its efficiency. So now when your Royal Oak service technician tells you its time to replace your PCV valve, you will know what he's talking about. If you have had your car for a while and this is the first you've ever heard of a PCV valve, ask your technician to check yours out or call TLC Custom Exhaust Brakes & Tires at 248-541-8300.

TLC Custom Exhaust Brakes & Tires
1735 N Main St
Royal Oak, Michigan 48067
248-541-8300
http://www.tlcautocareroyaloak.com

Need Service?

More articles from TLC Auto Care

The Light Nobody Wants to See (Check Engine Light)

April 28, 2024

You've probably had your Check Engine Light go on. Then it goes off and you figure, hey, whatever the problem was, it's gone now and I don't have to worry about it. Well, the problem may have gone away and it may not have. Your vehicle likely has one of these warning lights on the instrument pa... More

Fuel Saving Tip: Car Weight and Your Michigan Driving

April 21, 2024

Weight is the enemy of fuel economy. Everyone from Royal Oak knows this makes sense.Some of us in the Royal Oak area carry a bunch of unnecessary weight, and I'm not talkin' what you see in the mirror.Guys: sports equipment and tools. Ladies: well, just take a look around the passenger compartmen... More

Read a Good Tire Lately? (Tire Wear)

April 14, 2024

There's lots of good information to read in books and online. You might not know that you can also "read" your tires and learn a lot about what shape they're in and if they are in need of attention. It's important to know how your tires are doing because a tire failure can be very dangerous to y... More