Back to all

PCV Valve Replacement

August 28, 2022



Hello Lockport, 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. Lockport 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 Illinois 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 Lockport 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 Tuffy Tire & Auto Service Center Lockport . Fortunately, PCV valve replacement is both quick and inexpensive at Tuffy Tire & Auto Service Center Lockport. 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 Lockport 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 Tuffy Tire & Auto Service Center Lockport at 815-838-3700.

Tuffy Tire & Auto Service Center Lockport
600 E 9th Street
Lockport, Illinois 60441
815-838-3700

More articles from Tuffy Lockport

Getting Off to a Running Start (Starter Replacement)

January 18, 2026

When you start your vehicles engine, theres another motor that makes that whole process possible. Its called the starter, and its a small electric motor that gets your vehicle running. As you can imagine, its quite a chore for a little electric motor to turn over the big engine that powers you... More

You Are the Fluid Detective! (Leaking Fluids)

January 11, 2026

When you see some liquid sitting underneath your vehicle, your mind starts churning. Is that normal? Is that something serious, or did I just spill my drink? Heres a quick list of what those fluids look, smell and feel like, as well as what they might be. No, we dont recommend you taste them to ... More

Don?t Skip Out on These! (Vehicle Maintenance Items You Should Never Postpone)

January 4, 2026

Maybe that little sticker on your windshield is giving you the reminder that its time for your vehicle to have an oil change. Youve thought, Aw, I can skip this one and save myself a little money. When it comes to things you should never ignore on your vehicle, timely oil changes are number one... More