Yesterday we cleared out the PCV orifice on our 2.4 Ecotec eAssist (hybrid), which is similar to the 2013 Malibu hybrid (2013 Buick LaCrosse). There is a TSB with factory recommended testing and repair procedures for that PCV orfice.
To save time, we used an alternative cleaning method found on the internet. We did not pull the intake manifold but carefully drilled a 1/8" access hole into the OUTSIDE (only) of the manifold, inserted a big paper clip into the PCV orifice to clear carbon from the small orifice, carefully sealed with a 5/8" stainless sheet metal screw & o-ring. Took less than an hour outside (after planning and parts acquisition).
Car idles a bit better. The oil fill hole shows more suction (e.g. if we remove the oil cap the car will try to pull it back into place). Hopefully this reduces risk of rear main seal failure, reduces oil consumption risk, and engine will run cleaner.
Our manifold is glass reinforced nylon. The walls are thin and delicate so be very careful drilling as the manifold can crack which requires replacement.
Sealing the access hole is challenging. A sheet metal screw does not have ideal threads and expands/contracts at different rates from the nylon. Maybe a self-threading screw made for plastics would be a better choice but we didn't have access to one. Alternatively, some people adhered a nut to the manifold, then seal that with a short machine screw; it is tough to adhere anything to nylon, especially in the winter.
If we had to do it again, we would have drilled a hole smaller than 1/8". And used a wider silicone washer (rather than a small o-ring).
GM recommended a vented oil cap on some 2.4L engines to prevent blowing out the rear main seal (this seems to be a popular mod on the Chevy Terrain forums as an extra precaution). There is a TSB around that; not sure if it is applicable to the Malibu.
--> will post some links to TSB, videos, and forums once we get the ability to/
To save time, we used an alternative cleaning method found on the internet. We did not pull the intake manifold but carefully drilled a 1/8" access hole into the OUTSIDE (only) of the manifold, inserted a big paper clip into the PCV orifice to clear carbon from the small orifice, carefully sealed with a 5/8" stainless sheet metal screw & o-ring. Took less than an hour outside (after planning and parts acquisition).
Car idles a bit better. The oil fill hole shows more suction (e.g. if we remove the oil cap the car will try to pull it back into place). Hopefully this reduces risk of rear main seal failure, reduces oil consumption risk, and engine will run cleaner.
Our manifold is glass reinforced nylon. The walls are thin and delicate so be very careful drilling as the manifold can crack which requires replacement.
Sealing the access hole is challenging. A sheet metal screw does not have ideal threads and expands/contracts at different rates from the nylon. Maybe a self-threading screw made for plastics would be a better choice but we didn't have access to one. Alternatively, some people adhered a nut to the manifold, then seal that with a short machine screw; it is tough to adhere anything to nylon, especially in the winter.
If we had to do it again, we would have drilled a hole smaller than 1/8". And used a wider silicone washer (rather than a small o-ring).
GM recommended a vented oil cap on some 2.4L engines to prevent blowing out the rear main seal (this seems to be a popular mod on the Chevy Terrain forums as an extra precaution). There is a TSB around that; not sure if it is applicable to the Malibu.
--> will post some links to TSB, videos, and forums once we get the ability to/
