Read this entire page before purchasing a PCV Fix/Upgrade Kit!
These fix/upgrade kits apply to the following vehicles with the GM 1.4L Turbo LUJ/LUV/A14NET/B14NET engine:
  • 2011-2016 Limited 1.4L Cruze
  • 2011-2019 Chevy Sonic/Aveo
  • 2013+ Chevy Trax
  • 2013+ Buick Encore
  • 2011+ Opel/Vauxhall Corsa (Turbo only)
  • 2009+ Opel/Vauxhall Astra J (Turbo only)
  • 2010+ Opel/Vauxhall Meriva B
  • 2011+ Opel/Vauxhall Zafira Tourer
The 1.4L Turbo engine (LUJ/LUV) in the Chevy Cruze/Sonic/Trax and Buick Encore has a check valve in the intake manifold that has a 100% failure rate. Out of warranty, it can cost more than $350 to replace. There is no redesigned part for this (at the time of this post's writing), and new intake manifolds are still failing. The Dorman intake manifold reportedly has the same flawed design and is susceptible to coking, clogging, and check valve cracking, as reported by other 1.4T Owners. The newest V3.4+ PCV fix kit is less expensive, more durable, easier to install, and more easily serviceable than any other option.
DISCLAIMER: This solution has been tested, proven, and is generally considered reliable. To ensure a proper install, MAKE SURE YOU READ AND UNDERSTAND EVERYTHING IN THIS POST. Neither I nor CruzeKits.com nor CruzeTalk.com accept any liability for what happens during or after the installation of this kit. Proceed at your own risk. This is a kit that is being offered for your convenience. It is your responsibility to ensure that the components are working correctly and remain in good operating condition to prevent any issues. It is your responsibility to ensure that the components are clean (such as the check valve) to ensure there are no potential issues.
Read the first post on the following thread, which explains how our PCV system works and will help you understand the solution better: https://www.cruzetalk.com/forum/34-gen1-1-4l-turbo/175793-cruze-1-4l-gen1-pcv-system-explained.html
The basic principle is simple. You have two chambers; the intake downstream of the throttle body, and the PCV chamber. You need to allow gas to freely flow from the PCV chamber into the intake chamber when the engine is under vacuum (not producing boost), but block that flow of gas when the engine is producing boost. The OEM intake manifold check valve serves this function well, while it works, but the check valve stops sealing well after a few thousand miles, producing an audible boost leak, sometimes disappears altogether, or gets stuck and no longer produces vacuum on the crankcase. Failure of the intake manifold check valve usually does not trigger a check engine light on its own, but can contribute to other faults. This solution offers you the ability to cleanly retrofit a durable, leak-free external check valve that can be serviced easily should the check valve itself ever fail.
Benefits to the fix kits are: - Extremely robust, overbuilt components that ensure many miles of trouble-free operation. This kit use only high end components that resists chemical degradation, gumming, and blockage while also being easy to clean if needed.
  • Eliminates boost leak caused by aged, worn, or clogged OEM check valve by replacing it with a high quality, high heat resistant external check valve. 
  • Solves for loss of crankcase vacuum caused by stuck/clogged OEM check valve.
  • Solves boost leak, loss of power, poor fuel economy, and oil consumption caused by missing OEM check valve.
  • The new external check valve is easily accessible for cleaning, and can be replaced for $5-15
  • Stops oil consumption caused by missing check valve. Oil consumption will cause carbon build up on the piston crown and ring lands, which can cause detonation and piston damage.
  • Much longer lasting valve than the OEM check valve due to more robust design.
Check out the original discussion thread, containing over 40 pages and nearly 500,000 views, where this PCV fix kit was introduced and reviewed: https://www.cruzetalk.com/forum/34-gen1-1-4l-turbo/189402-gm-1-4l-turbo-intake-manifold-pcv-valve-fix-kits.html
CruzeKits.com PCV Fix kits address failure of GM Intake Manifold Part 25200449

Overview of the 1.4L Turbo PCV System

Chevy Cruze, Chevy Trax, Chevy Sonic, and Buick Encore