What is PCV Valve? Do I need to replace it on my G35??

[Smartidiot]

Hi,

I am not sure if this question has been asked before.

But can anyone here briefly explain to me what a PCV valve is and is it necessary to replace them on my 2004 G35 Coupe (currently @ 100,000km)?

If the answer is true.. how come I cannot fidn it on the Infiniti service manual??

Thanks in advance!Robin

[Sentientbydesign]

PCV Valve- Positive Crank-Case Ventilation Valve

Basically the valve is part of the PCV system which allows crankcase gases to exit the crankcase and be reintroduced into the intake plenum for combustion. Prior to the PCV system, the crankcase was allowed to vent into the atmosphere and oil/fuel were allowed to leak all over the streets/highways.

The valve sits on the crankcases and provides 1 way flow of crankcase gases.

Should be a cheap, relatively simple repair.

[mrsmithGrider]

It's really funny that this is brought up because the place where I go to get my car waxed at, which is also also works on cars had a G35 that it was fixing. While waiting on my car to be fixed i saw the car jacked up through the glass windows. I went over to ask the manager what was wrong with the car. He told me it was a 2003 G with 130,000 miles on the dash with i think he said blown head gaskets....he said he opened the plenum up and it was filed with oil. He said he thinks the PCV valved failed and was never replaced and then asked me if I had ever changed mine. I have 80k miles on the dash and has never replaced mine. I am very stern about my maintenance, but i never heard of this. I know one thing, I would not trust my car with them. He said the engine was blown and that he was ordering a used one to install himself. I was thinking in my mind, who the hell would let their car's engine be replaced by a non certified mechanic. . My question is, is this something that can ruin your engine if it fails?

[fbpem1]

the pcv valve won't ruin your engine it will either stick closed or stick open, either making the car smoke or making it run like not crap but different.

Headgaskets i have seen go a few times and have replaced a handful of motors as well since redoing the heads and dissabmeling the motor down to a short block is a waste of ****ing time then sending the heads to the machine shop this that and the other is just outlandish. The long and short of it a pcv valve isn't going to blow your headgaskets.

I have seen a few G's with a bad PCV valve and a few of the other cars, i don't reguarly replace them, theres only 1 valve on that motor and thats the passenger side valve cover, comes off with a 26mm i believe can't remeber the size off hand.

[Jacko3]

Smartidiot:

I replace my PCV Valve every year. It should be part of a routine maintenance schedule. How people do tune up and yet miss the PCV valve is a little surprising to me. It isn't the big stuff that kills a car, its the small neglected stuff that does. Neglect, in my book is the same thing as abuse.

Driving a G-35 hard is not abuse in my book---it is simply driving the car the way it was meant to. But if you drive hard, then it is a must to do routine maintenance annually--thats the price one pays for driving hard.

If you put close to exactly 30K annually on your car----please, change the radiator fluid annually, change the PCV valve, change your differential fluid, change your oil at 3,000 miles, change your after market air filter at least once every six months, it won't hurt to get all the belts replaced as well even it appears excessive at this point, change your brake fluid every second or third change of front brake pads (I change brake pads twice a year with OEM pads), change automatic transmission fluid every year if you have one. And if you really have the money, do the spark plugs as well. If I wasn't prepared to do all this stuff, I won't be driving hard to begin with.

[Sentientbydesign]

^^^

I respect Jacko's advice, but this is majorly overkill for normal driving. PCV valves usually have a very long life expectancy and the oil vapor from the crank case keeps them well lubricated.

I would stick to the recommended service intervals unless you drive like a Mafia hired transporter

[Jacko3]

^^^

I would stick to the recommended service intervals unless you drive like a Mafia hired transporter

Yep, driving like a Mafia hired transporter will do it.

[Sentientbydesign]

On a side note, I once (honestly) wanted to be "driver"

[Jacko3]

Nate:

Be a driver, how so? Do you mean a race car dirver? You know, I once said, I would love to have a part-time job as a test driver for Nissan Motor Company. Man, that would really be a dream part-time job, and I would probably do it for free so long as they pay for airfare, hotel, rental cars, and any other contingencies.

[Sentientbydesign]

No, as in Mafia/hitman driver.

[Guju Rider]

i was looking to find out how many ft.-lbs or in.-lbs you would torque down the pcv valve down to..i've just received my spark plugs so i thought if im gonna work on that..might as well order a valve also and install it at the same time.