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

 

If memory serves me, there is no PCV on the VQ engine.
A quick call to the dealer will confirm tho.

All it is is a mechanical valve that controls ventilation flow (air) throughout the engine to keep combustible and polluting gases moving thru the engine.

I believe that function now is computer controlled.

Colin

 

It's a positive crankcase ventilation valve. Here is a link to an explanation:
http://en.wikipedia.org/wiki/PCV_valve

I'm not aware of what the service interval is in the G. Like Colin said I'm not sure about having one but the dealer can confirm. Some folks have built a home made catch can.

In any case a PVC valve is a cheap and easy DIY.

 

vq does have a pcv. they are very cheap... i'm thinking around 15-20$. should look like a small plastic valve. i didn't know they had to be replaced though.

edit: i've attached a page from the manual

 

Thanks, Roman....I'll have to remember that.

C.

 

Thanks Roman. Now that you pulled it up I think I recall seeing it when I did my spacer install.

It used to be a more common tune up replacement item.

 

I believe it was more than $20, around 35-40 bucks. I replaced mine, had a bit of oil in it (was told it was normal). Didn't notice too much difference after changing it. It's on the left bank closest to the front of the 3 sparkplugs (looking at engine from the front).

 

^ good info Randy.

 

$40 ? that's way too much. it's just a small cheap plastic valve. i can't believe company's still rip people off like that.

i looked it up on the infiniti parts usa website... it's $8.73
go to http://www.infinitipartsusa.com/spla....cfm?siteid=55 and search for pcv.

 

I could be wrong on the pricing, but I did recall being a little surprised at the cost of this small item. I have the receipt somewhere at home, I'm just feeling a bit lazier these days. It's the 1st symptoms of the OF syndrome I believe, followed by random losses of non-G related memory etc.

I also recall that if you took yours out and shook it, and you hear a little rattling, then it's functioning perfectly. Otherwise, a replacement might be good. Good for the environment and fellow tree huggers.

If you want a pic of this valve, let me know, I'll snap a pic of it this weekend if I can remember.

 

^ yes, if you shake & hear a rattle, you're OK. this is a very basic little plastic valve that is always less than $15. if your supplier is charging you more, find a new supplier.

 

we've been replacing these like crazy on the G37's if people run regular or midgrade gas

 

Why? What sort of problem is it causing? Just curious...

 

Most likely incomplete combustion of the lower octane fuel . JMO

 

I wonder if clogged PCV valves are the cause of many folks' oil consumption issues???