Checking PCV valves

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Location
California, USA
I checked the service manual for my Civic and found that there was a simple procedure for inspecting the PCV valve. I thought I'd check it out since the car burns a little oil and that's one possibility. The instructions said to pinch the PCV hose with the engine idling and listen for a click. I couldn't hear any clicks, even with my stethoscope, but I'm not sure whether that's because the valve is malfunctioning or because .. it's kind of hard to hear a small click over the engine noise. What were they getting at with this test procedure? Why would the engine have to be idling for it to click? Should I have to pinch the hose totally closed? I'd rather not remove the valve to check it because it's kind of hard to get at.
 
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1,606
Location
Oahu, Hawaii
Its probably a way to tell if the valve is moving freely and and gunked up without removing it off the engine. Shaking a PCV valve will not tell if it's still good. The spring inside it may wear over time. Try changing it and see if it solves your oil burning problem.
 
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Messages
549
Location
New Mexico, U.S.A.
I would probably change it out... a PCV valve for my Civic runs about $20. Then you can play with the old one at your leisure, clean it out, and possibly reinstall it later in your car's life. I should probably buy the service manual myself. How long did it take for the manual to pay for itself in your case?
 

rationull

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I'm not sure I'd say it's paid for itself yet, technically. I've referenced it for various things (torque specs, rear stabilizer bar upgrade) and looked up wiring info for some people online a couple of times. When it comes to things like brakes it'll come in a little handy but honestly with all the forum help out there I wouldn't say the manual is necessary. I got it because I'm anal about torque specs and I just wanted to be able to look at it. The sections about the EFI system are pretty interesting, and it's got lots of cool diagrams. For what it's worth, it's a very nice manual. Much easier to follow than the manual for our Mazda3. It also tends to give instructions using jacks and jack stands, and give you alternative options that don't involve the special Honda diagnostic computer where possible so it's very usable for the home mechanic. If you don't buy it, but need some info out of it, you can always PM me :)
 

rationull

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 Originally Posted By: tropic
I would probably change it out... a PCV valve for my Civic runs about $20. Then you can play with the old one at your leisure, clean it out, and possibly reinstall it later in your car's life.
Yeah, the only reason I'm trying to avoid it is the [censored] cowl cover is a PITA to get behind. I think the PCV valve is placed such that with the right (long) needle nose pliars and the right length socket extension you can get it out without removing the cowl cover, though. At least it's better than on the Mazda where it's under the intake manifold!
 
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19,479
Location
Chicago Area
Checking by the 'pinch' methhod, or shaking the PCV valve tells you nothing. Except maybe that it isn't fully stuck. All sorts of things can still be wrong with it. They are not a high wear item, but they do have seats , and maybe a spring. Bypass orfices, or normal flow may get restricted by accumulated doo-doo in them.
 

JHZR2

Staff member
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44,823
Location
New Jersey
If it is anything like the one on our old integra, it's so cheap that removal may well equal mandatory replacement. If I was checking it, i'd do it right, and for the most part would replace it once going through that...
 

rationull

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I'm not opposed to replacing it, but I don't really want to do it for no reason. At 36k miles on the car I doubt the valve is worn out, and with fairly consistent oil burning patterns it could just be my hilly high load commute coupled with a relatively small engine that's causing it. I was mostly curious as to whether you're really supposed to be able to hear a little click over the engine noise.
 
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24,412
Location
Central Florida
On our old Civic, I cracked open the original PCV valve with about 120K miles and it was very clean, just a tiny bit of oil inside, ZERO grime built up inside. To be honest , as long as you change the oil often, that PCV stays spotless. There is no need to change your PCV valve on your Civic. Just keep adding some make up oil if your engine consumes oil. Every engine is different, our 2007 Civic doesn't consume any oil even after an 11K OCI on Mobil 1. Also read this: http://www.tegger.com/hondafaq/pcv-replace/index.html
 

rationull

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California, USA
Easy to say "every engine is different" and I do accept that but the psychological effect of reading how so many cars "don't burn a drop between changes" can be quite severe for a BITOGer whose new[er] car uses oil! If I had to guess my laziness will prevail in this case, though. I definitely don't want to change it until I switch to GTX for the next OCI and see if it affects the usage rate at all. Also check check around under the car to make sure I haven't missed any leaks.
 

rationull

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Maybe. I can't complain too much, honestly. I'll measure the consumption more attentively next time around but the car gets a lot of high load driving and high vacuum driving given my commute route. I really just posted this because I was curious as to how you're supposed to hear the PCV valve click over the engine idle.
 

hal

Messages
393
Location
NC
pull it off the intake manifold, remove the hose and shake it. if it clicks its good. if its a little oily spray it out with carb cleaner and it'll be good as new.
 

rationull

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 Originally Posted By: Vaca
How much oil does it use?
To be honest I haven't been as precise as I should be when measuring so far, but I'm going to pay more attention during my next OCI. I think it's been somewhere between 1 and 2 quarts in a 6000 mile OCI on my current fill of YB Pennzoil. I think it was somewhat lower previously on previous OCIs with Motorcraft. Not a big deal but more than most people report on newer engines.
 
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373
Location
South Central PA
 Originally Posted By: rationull
 Originally Posted By: Vaca
How much oil does it use?
between 1 and 2 quarts in a 6000 mile OCI
if it's 1 quart, no big deal, I wouldn't bother with trying to get to the PCV valve, or really anything...but 2 quarts in a newer Honda, something's not right, and I would certainly check the PCV valve (even if it's a pain to get to), and other obvious things.
 
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