PCV Valve studies

[JHZR2]

Hi,

I studied the PCV valves for the 4.3L v6 (GM). My application is a 98 Chevy S10 ZR2.

Fram/wal-mart: loose innards. spring seems soft

purolator: Stiffer spring, smaller diameter innard, lower QC appearance

Deusch: Loose innards, appears about the same as fram

GM: Higher QC appearance, siffer spring

I dont know if the stiffness of the spring that keeps that inner plate tight really matters, since at idle, its sucked all the way to the top anyway.

Perhaps the size of the inner plate effects airflow... the engine seemed less likely to shake slightly at idle, with the smaller inner plates in the purolator... though the GM one worked well, and the inner plate was larger like in the fram unit. This may be related to engine temp too.

So it seems like all but OEM are about the same, all have their plusses and minuses, but all about the same, IMO. Stiff spring and small diameter inner piece may contribute to smootheridle... but it may betterbe due to the overall design/shape of the inner valve, so that a good seal is made at idle.

Maybe this isnt worth a thing...

JMH

 

[PandaBear]

same observation on my integra, the OEM seems well build and the Fram looks like junk, works but fit and finish is horrible.

 

[JHZR2]

Integra PCV valves are worse than most, because access is difficult... get a flimsy valve, and itll break quite easily.

My GF has a 94 integra, and the valve broke during instalation! The problem is that the valve is a flimsy plastic, glued halfway.

OEM is definitely important for that application.

I'm not sure if fram was all that much 'junk' compared to any other aftermarket PCVs. All had their flaws, the key thing was that all had their storngpoints too, and the GM valve had all of the strongpoints which appeared to me to be important, with none of the apparent flaws liek weak spring, undersized check valve, etc., etc.

JMH

 

[Matt_S]

I was experiencing shaky idle with a non-OE PCV valve in my 3800 V6. I switched back to OE and the problem hasn't returned. It seems disturbing to me that something that can potentially cause unwanted vacuum leaks and all the problems that go along with them would be so carelessly manufactured. I'll be going back to GM for all my PCV valves from now on.

 

[Jim Spahr]

On the Impala SS forum, they highly recommned using the GM version of the PCV and the O2 sensor as well. On other mtce items such as brake pads, they will rec. many other brands and varieties. I think one reason for this is the after market manuf. try to make one model PVC fit as many different vehicles as possible. One size fits all' to reduce the amount of models to cover the entire vehicle universe.

 

[JHZR2]

I just noticed that the deutsch (autozone) valve is the same as the fram!

It says made in the USA, but the QC does not seem to be there.

Purolator seems thebest non-gm part, i guess... I have to look and see the differences between all of them and a new GM part...

JMH

 

[blupupher]

quote:

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Originally posted by JHZR2:
I just noticed that the deutsch (autozone) valve is the same as the fram!

...

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Hmm, the one for my Hyundai (deutsch) is all metal and looks and seems identical to OEM. I have not seen a fram to compare to though.

 

[JHZR2]

well, in design and construction material they seem the same as OEM... but quality definitely differs!

The part numbers and valve stampings are identical fram to deutsch.

Purolator or GM seem the best for my application, as of now...

JMH

 

[PandaBear]

JHZR2,

My integra is OBD2 so it is as easy to replace as any simple car, just pull it out by hand.

 

[BlazerLT]

I don't remember my pcv valve having a spring?