Blow-Out Protection for PCV Failure

ken-clifton

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Background: For different failure modes of the multiple check valves in the PCV system on the 1.4L Turbo engine (LUV) used in the Buick Encore, Cruze, and Sonic : 2011-2016 Cruze 1.4 PCV Valve Cover/Intake Manifold Issues

I have been looking for something to protect against pressurizing the crankcase and potentially blowing out oil seals, gaskets and the rubber disc on the valve cover that frequently happens when the non-replaceable rubber flapper check valve in the plastic intake manifold fails. According to most sources folks are lucky to get 60K before that happens (research for yourself).

When the rubber flapper check valve made into the intake disappears or fails, the turbo boost in the intake can pressurize the crankcase. Of course this can cause all kinds of issues with crankshaft seals, valve cover and other gasket failures, etc.

A *normal* valve cover breather would not work because in normal operation, there is a vacuum regulated by the diaphragm on the valve cover, with vacuum either from the intake or the turbo inlet. Such a breather would cause a severe vacuum leak. But, several performance companies have started making oil caps with a breather AND A BALL CHECK VALVE.

The replacement oil cap (w/check valve & breather) basically does nothing as long as the PCV is functioning normally... When (not if) the check valve made in the plastic intake manifold fails, the check valve in the new oil cap/breather will vent that turbo-boost pressure to protect the engine seals -- similar to a blow-off valve on a pressure cooker.

The trick it seemed was to find something that would work with the 1.4L turbo engine on the Encore. Starting in model year 2017 (and later replacement valve covers for earlier years), the valve covers come with a locking collar that implements the old-style double-helix GM oil cap design -- earlier years had an oil cap with two tangs -- not the double-helix.

After some looking on eBay and other sites, there just did not seem to be anything to work, but the folks in Florida worked with me to basically take a cap for GM and enlarge one of the openings to the helix so that the billet aluminum fits the 1.4L Turbo perfectly. If interested visit: CFM Performance Billet Valve Cover Breather for 2016-2018 Buick Encore 1.4L
(I do not work for them -- but am thankful for their help)
 
Thanks for the heads up about potentially serious failure issues with our Encores and the link to the aftermarket oil cap breather with a check valve. The fellow on the Cruze forum provided a lot of useful info about PCV issues, but I was wondering, since he stated he has experienced a 100% failure rate on the cars that he has come across, how many cars he has actually come across, and one might find other info confirming this failure rate, such as service bulletins,etc. I was also wondering if you were thinking about getting the fix kit in addition to the the preventative oil cap breather with check valve you linked? One more thing, since the post from the Cruze forum was in 2017edit🙁 just saw that post was edited in late 2018), I was also wondering if you know if these failure issues also affect 2018/2019 Encores? It's madness that Buick/GM has not adequately addressed this high failure rate engine problem.Thanks, again.
 
Hi Steveyo, I am going to try to answer your multiple questions:

1) how many cars he has actually come across, (failures)?
If you think about a PCV valve, they are all going to fail eventually. It is just unfortunate that GM integrated this check valve into the plastic intake manifold where to stay OEM, you must replace the whole manifold. As far as actual failures it is a very big number. Just search the Sonic, Cruze or Encore forums' postings to see how many intake manifolds have been replaced. And, the narrative goes something like: (1st) valve cover replaced due to leak or blown diaphragm on it, then (2nd) they replace the intake, because that was what really caused the valve cover to blow out. Finally (3rd) they replace the crankcase seal because the over-pressure caused it to start leaking. There are plenty of stories right here. Just take the pattern I just described and look through the posts in this very drivetrain section.

2) Does this affect the 2018/2019 Encores?
It affects my 2018 Encore, but two different engines are used in the Encore. The engine that is the subject of this failure mode is the (LUV) Vin Code "B" 1.4L Port-Injected turbo. Not the high-output (LE2) 1.4 GDI Turbo Vin Code "M". I really don't know enough about the LE2 engine to know where the check-valve for the PCV is located since I do not have that engine.

3) Where you thinking of getting the PCV fix kit?
Short answer, I have one sitting on the shelf in the basement along with an aluminum intake manifold. Since my Encore is under warranty for four years, I am not doing any modification to it, except to protect it with the oil cap that basically does nothing until an over-pressure of the crankcase happens. Perhaps with that protection, it will just issue the check engine light without blowing out a bunch of extra parts, and I can then get the intake replaced if it happens under warranty. The aluminum intake is very nice but pricey -- see: Sonic Intake Manifold
 
Thanks Ken, It is a shame that GM didn't make the extra little effort to make the check valve much easier to replace. I failed to mention that I have a 2019 with 1.4 Turbo vin code "B" and only 2,000 or so miles on it, and so I'm covered for for a long time, yet I like to be prepared for what may be coming. I appreciate your search for and link to the modified oil cap, which I think I will purchase to be somewhat safe. The aluminum intake manifold is a bit pricey, but it's sure pretty in addition to what must be its superior build.
 
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Ken, thanks for all the info on this. I'm going to have to do some digging as our 2016 has the high output 1.4.
 
Ken, the OP, mentioned:

"The trick it seemed was to find something that would work with the 1.4L turbo engine on the Encore. Starting in model year 2017 (and later replacement valve covers for earlier years), the valve covers come with a locking collar that implements the old-style double-helix GM oil cap design -- earlier years had an oil cap with two tangs -- not the double-helix."

I was wondering if anyone knows why and for what purpose the valve cover and oil cap were changed and installed on the newer Encores such as my 2019 Encore 1.4 turbo that has the integrated tube extension and and newer cap, which were not used on the earlier Encores with valve covers for engine VIN B w/o tube extension? I assume it was an improvement, but wonder what the improvement is. Thanks.
 
My other half just got a 2016 Buick Encore today with the suspect LUV engine (she quickly learned about it, luckily from a friend of her's who's a mechanic and overheard her) and so would be interested in investigating the venting oil cap. Any links to reputable vendors??? Please and thank you!
 
My other half just got a 2016 Buick Encore today with the suspect LUV engine (she quickly learned about it, luckily from a friend of her's who's a mechanic and overheard her) and so would be interested in investigating the venting oil cap. Any links to reputable vendors??? Please and thank you!

The following link is also in the OP's post. This is the only vendor I know of. This same vendor used to and may still sell this breather on an eBay site.

CFM Performance Billet Valve Cover Breather for 2016-2018 Buick Encore 1.4L
 
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It is available on Ebay, but direct from CFM gets you free shipping. On Ebay shipping is $5.00 on top of the price, which is not discounted.
 
My PCV valve is still there after 97000kms. Picture taken with my endoscope.

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Hmm--looks as if it's getting ready to pop out. Just joshing.😉 I do find it baffling why so many intake check valves fail at relatively low miles while others seem to be ok at 60,000 or 100,000 miles. Perhaps how one drives, the type of weather conditions, etc., affect the outcomes.
 
I bought a valve cover and replaced it myself. $64 Cnd

I have not looked at it but from what I've read it's not terribly difficult. It's not like it's a head or a timing chain.
 
Yes, a round rubber gasket, you just lightly grease it and insert it in the cover then install. It comes with the cover. You don't have to grease it but I do.
 
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Hello i replaced two valve cover and pressure is building up and making oil come out the left hand side of the valve cover
 
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