Symptoms of a Bad or Failing PCV Valve Hose

The Positive Crankcase Ventilation (PCV) valve hose transfers excess gasses from the crankcase to the PCV valve. From there, it is added to the intake manifold and used by the engine. If the PCV valve hose breaks, the gas will not be transferred back into the engine, and your vehicle will be less efficient and have increased emissions. There are a few symptoms to watch out for when you have a bad or failing PCV valve hose.

1. Poor fuel economy

If the PCV valve hose is clogged or has a leak, it may cause poor fuel economy. This is because the vacuum on the intake side of the cylinder head will not be able to properly signal the correct amount of fuel that needs to be fed into the engine and can result in a lean or rich engine condition. If you suspect a PCV valve hose is the reason you have been getting poor fuel economy, contact the professionals at YourMechanic to have your PCV valve hose replaced.

2. Check Engine Light comes on

The Check Engine Light may come on for a variety of reasons, and one of them is a failing PCV valve hose. This is because the PCV valve hose works directly with your engine to ensure everything is working properly. The mechanics at YourMechanic can diagnose the exact reason the Check Engine Light is on, whether it is the PCV valve hose, the PCV valve, or a combination of parts.

3. Misfiring while idling

Another symptom of a bad or failing PCV valve hose is your vehicle will misfire while it is idling. This can be from a loss of vacuum due to the hose not working properly because of a leak, the hose being pinched, or becoming clogged from buildup over time. A misfire will sound like the engine has a vibration to it is a sign it is not running properly.

4. Noise from the engine

If you hear a hissing sound from the engine, it is time to get your vehicle looked at. The PCV valve hose may have a leak in it, which is causing the hissing sound. Leaving this for too long can cause misfires, rough running, vacuum leaks and you will have a more extensive repair on your hands.

YourMechanic makes getting repairs to your PCV valve hose easy by coming to your home or office to diagnose or fix issues. You can book a service online 24/7. YourMechanic’s qualified Technicians are also available for any questions that may arise.


Next Step

Schedule Vehicle Engine Mechanical Inspection

The most popular service booked by readers of this article is Vehicle Engine Mechanical Inspection. Once the problem has been diagnosed, you will be provided with an upfront quote for the recommended fix and receive $20.00 off as a credit towards the repair. YourMechanic’s technicians bring the dealership to you by performing this job at your home or office 7-days a week between 7AM-9PM. We currently cover over 2,000 cities and have 100k+ 5-star reviews... LEARN MORE

SEE PRICING & SCHEDULING

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Recent Vehicle Engine Mechanical Inspection reviews

Excellent Rating

(156,506)

Rating Summary
146,691
5,341
1,090
770
2,614
146,691
5,341
1,090
770
2,614

Pete

16 years of experience
192 reviews
Pete
16 years of experience
Ford Taurus V6-3.0L - Spark Plugs - San Diego, California
All worked out great!
Plymouth Caravelle - Exhaust Gas Recirculation/EGR Valve - San Diego, California
Pete is Great! His work is exceptional and he is honest and professional.

Tien

23 years of experience
903 reviews
Tien
23 years of experience
Ford Focus L4-2.0L - Fuel Pump - Fremont, California
As always, Tien did the job very well. He's an honest guy, expert and friendly. That's my honest opinion. If you guys are looking for a good mechanic, this guy is A number 1!!!
Honda Civic - Crankshaft Position Sensor - Oakland, California
Thanks Tien.

Rusty

23 years of experience
462 reviews
Rusty
23 years of experience
GMC Sonoma L4-2.2L - Vehicle Engine Mechanical Inspection - Arlington, Texas
Great overall impressions. Vechile is driveable and runs terrific now.

Raymond

37 years of experience
267 reviews
Raymond
37 years of experience
Cadillac Brougham V8-5.7L - Vehicle Engine Mechanical - Las Vegas, Nevada
Talent and passion for what you do in any field is critical, Raymond seems to have both. I have dealt with many Mechanics in my day Raymond is one of the best. Thank you sir.

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

Related articles

Symptoms of Bad or Failing Differential / Gear Oil
If your car has exceeded its gear oil service interval, or if you hear the differential whining, you may need to replace the differential/gear oil.
How Exhaust Systems Work
It It all starts in the engine In order to understand how the exhaust of a vehicle works, there must be a basic understanding of the engine as a whole. The internal combustion engine in its simplest form is a...
Why Does My AC Rattle When I Turn It On?
Common reasons why a car AC system makes a rattling noise is due to a failing AC compressor, worn serpentine belt, or worn out AC compressor clutch.

Related questions

Screeching metal sound

The power steering fluid you keep adding has to be going somewhere and it most likely leaking from one or more places. Typically the power steering pump, high pressure line and power rack and pinion are common failure items. Have...

Car misfires; loud engine noise

If your vehicle is misfiring, and making lot's of noises, there is probably some sort of engine performance related problems. Symptoms like these can be caused by the need for a tune up, to a problem with one of the...

Loud clunk, smoking and leaking, car shakes

Hi there, thanks for writing in about your 2001 Hyundai Elantra. This sounds serious - like the engine broke a connecting rod, which punctured the oil pan, and dumped the oil. Checking your oil level with the engine dipstick will...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (855) 347-2779 · hi@yourmechanic.com