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In the interest of providing at least some summary of what is already known for any PCV related moisture/blow by product issues on the GM 2.4L LAF, LEA or LUK engines, here is a start as a summary along with a list of some threads at the end of it that deal with previous threads that may contain valuable information previously discussed when more user traffic was common on this forum.

Related documents:
https://gm.oemdtc.com/Recall/SB-10057977-8108.pdf


So, for all who are interested, here is a summary of what previous threads and owner experiences have learned about the GM LEA (LAF, LUK) 2.4L 4 cylinder Gasoline Direct Injection PCV system and issues. A bit of this info also pertains somewhat to the 3.6L LFX V6 engine.

This summary hopefully will provide at least a basis for understanding the PCV items listed below. As with any discussion, there may be more to be discovered as time and experience goes on.

1.) As on most modern engines, the 2.4L has both a "clean" air side and a "dirty" air side of the PCV system. The clean air side is via a tube essentially run from the valve cover area to what GM calls the "Air Duct" or plenum. This Air Duct provides baffling, noise reduction and some tuning of the air intake system.

2.) The Air Duct or plenum, has internal chambers through which air from the air cleaner flows to the Throttle Body and intake manifold. There is a small molded pocket or catch container immediately below the inlet connection of the "clean air" line from the previously mentioned valve cover. This clean air side is not to be confused with a PCV vent line like older engines may have had. This air line, under certain conditions, can pass small amounts of water/oil vapors into the Air Duct which connects to the Throttle Body. But little to none usually deposits anything into the Throttle Body under normal engine operation. At least one owner suggested modifying the fresh air line by cutting it and removing a dip or low spot in the tube that may hold moisture/oil vapor and freeze. It would be a good maintenance practice to remove and clean this air tube and the inside of the Air Duct perhaps annually, to insure clean operation.
The water/oil emulsion in cold or even humid weather has a yellowish appearance.

3.) The PCV orifice located internally in the intake manifold is of the main problem concern for the 2.4L LEA, LAF, and LUK engines. This is not a serviceable PCV "valve", but rather just a small metering hole which passes blow by combustion by products of water, oil, and burnt fuel vapors.


This internal PCV orifice passes the majority of the blow by products into the intake manifold and is what is responsible for any intake valve "coking" of carbon deposits. But more inmportantly, the PCV orifice has shown itself to get clogged by BOTH blow by product carbon build up and frozen water vapor in very cold (usually low double and singe digit F) driving conditions.

4.) A clogged or frozen PVC orifice has demonstrated the unfortunate result of blowing out rear main crankshaft seals in the 2.4L mentioned engines. So this is the major area of concern due to cost of repair and potential of immediate loss of engine oil which could result in severe engine damage and even seized pistons.

5.) There has been much discussion on the Equinox/Terrain Forum regarding the PCV orifice, blown main crankshaft seals and related issues for the 2.4L engine class.

6.) It has been suggested that some sort of pressure relief valve installed in the oil cap may help at least prevent crankcase pressure build up due a clogged or frozen PCV orifice and the catastrophic failure of a blown rear main crankshaft seal. See picture below:




7.)There is no practical currently known way to provide an oil/water vapor catch can on the "dirty" PCV orifice side of the PCV system for the 2.4L LEA, LAF, LUK engines such as can be done for the 3.6L LFX engines which have a traditional external PCV orifice in one valve cover. The 2.4L PCV issue is covered by at least two GM TSB or tecnical documents as well as an extended coverage for a failure.

Here is a a partial list of forum threads associated with these and other PCV issues:

https://www.google.com/search?q=Equinox+2.4L+PCV+site:www.equinoxforum.net&client=firefox-b-1&sa=X&ved=0ahUKEwjf37f1xaDZAhVK4GMKHdasDLoQrQIIXigEMAE&biw=1152&bih=606

https://www.google.com/search?q=GM+2.4L+PCV+failure+site:www.terrainforum.net&client=firefox-b-1&sa=X&ved=0ahUKEwjV6p3MwKDZAhVM0GMKHboMCdIQrQIINCgEMAA&biw=1152&bih=606

Some of the information in the video below is not entirely accurate and the author refers to a "recall" but is really extended special warranty and also related earlier TSB. Also, as indicated earlier in this posting, the problem was more likely caused by a frozen or clogged internal PCV orifice. . . not moisture/oil build up in the "fresh air line" he shows in the beginning of the video.

 
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Discussion Starter #43
In the interest of providing at least some summary of what is already known for any PCV related moisture/blow by product issues on the GM 2.4L LAF, LEA or LUK engines, here is a start as a summary along with a list of some threads at the end of it that deal with previous threads that may contain valuable information previously discussed when more user traffic was common on this forum.

Related documents:
https://gm.oemdtc.com/Recall/SB-10057977-8108.pdf


So, for all who are interested, here is a summary of what previous threads and owner experiences have learned about the GM LEA (LAF, LUK) 2.4L 4 cylinder Gasoline Direct Injection PCV system and issues. A bit of this info also pertains somewhat to the 3.6L LFX V6 engine.

This summary hopefully will provide at least a basis for understanding the PCV items listed below. As with any discussion, there may be more to be discovered as time and experience goes on.

1.) As on most modern engines, the 2.4L has both a "clean" air side and a "dirty" air side of the PCV system. The clean air side is via a tube essentially run from the valve cover area to what GM calls the "Air Duct" or plenum. This Air Duct provides baffling, noise reduction and some tuning of the air intake system.

2.) The Air Duct or plenum, has internal chambers through which air from the air cleaner flows to the Throttle Body and intake manifold. There is a small molded pocket or catch container immediately below the inlet connection of the "clean air" line from the previously mentioned valve cover. This clean air side is not to be confused with a PCV vent line like older engines may have had. This air line, under certain conditions, can pass small amounts of water/oil vapors into the Air Duct which connects to the Throttle Body. But little to none usually deposits anything into the Throttle Body under normal engine operation. At least one owner suggested modifying the fresh air line by cutting it and removing and dip that may hold moisture/oil vapor and freeze. It would be a good maintenance practice to remove and clean this air tube and the inside of the Air Duct perhaps annually, to insure clean operation.
The water/oil emulsion in cold or even humid weather has a yellowish appearance.

3.) The PCV orifice located internally in the intake manifold is of the main problem concern for the 2.4L LEA, LAF, and LUK engines. This is not a serviceable PCV "valve", but rather just a small metering hole which passes blow by combustion by products of water, oil, and burnt fuel vapors.


This internal PCV orifice passes the majority of the blow by products into the intake manifold and is what is responsible for any intake valve "coking" of carbon deposits. But more inmportantly, the PCV orifice has shown itself to get clogged by blow by BOTH blow by product carbon build up and frozen water vapor in very cold (usually low double and singe digit F) driving conditions.

4.) A clogged or frozen PVC orifice has demonstrated the unfortunate result of blowing out rear main crankshaft seals in the 2.4L mentioned engines. So this is the major area of concern due to cost of repair and potential of immediate loss of engine oil which could result in severe engine damage and even seized pistons.

5.) There has been much discussion on the Equinox/Terrain Forum regarding the PCV orifice, blown main crankshaft seals and related issues for the 2.4L engine class.

6.) It has been suggested that some sort of pressure relief valve installed in the oil cap may help at least prevent crankcase pressure build up due a clogged or frozen PCV orifice and the catastrophic failure of a blown rear main crankshaft seal. See picture below:




7.)There is no practical currently known way to provide an oil/water vapor catch can on the "dirty" PCV orifice side of the PCV system for the 2.4L LEA, LAF, LUK engines such as can be done for the 3.6L LFX engines which have a traditional external PCV orifice in one valve cover. The 2.4L PCV issue is covered by at least two GM TSB or tecnical documents as well as an extended coverage for a failure.
Here is a a partial list of forum threads associated with these and other PCV issues:



https://www.google.com/search?q=Equinox+2.4L+PCV+site:www.equinoxforum.net&client=firefox-b-1&sa=X&ved=0ahUKEwjf37f1xaDZAhVK4GMKHdasDLoQrQIIXigEMAE&biw=1152&bih=606

https://www.google.com/search?q=GM+2.4L+PCV+failure+site:www.terrainforum.net&client=firefox-b-1&sa=X&ved=0ahUKEwjV6p3MwKDZAhVM0GMKHboMCdIQrQIINCgEMAA&biw=1152&bih=606

Some of the information in the video below is not entirely accurate and the author refers to a "recall" but is really extended special warranty and also related earlier TSB. Also, as indicated earlier in this posting, the problem was more likely caused by a frozen or clogged internal PCV orifice. . . not moisture/oil build up in the "fresh air line" he shows in the beginning of the video.

This should be stuck at the top of the gen tech or engine topic area. Very well put together.
 

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By any chance, does anyone happen to know if gm fixed this issue on later models by enlarging the hole for the pcv? I will likely go the route of the pressure release for piece of mind - cheap reliable solution to something potentially catostrophic.
 

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By any chance, does anyone happen to know if gm fixed this issue on later models by enlarging the hole for the pcv? I will likely go the route of the pressure release for piece of mind - cheap reliable solution to something potentially catostrophic.

There has been no GM fix for the 2.4L PCV orifice issue that I am aware of as of this writing. Interestingly, the problem also is present on two versions of GMs 1.4L (and maybe 1.5L) engines as well. Although, those engines use a slightly different design, but results are the same. The PCV orifice gets clogged with carbon deposits or frozen with moisture in low double and single digit temperatures. Then the crankcase is pressurized with blow by gases and main seal damage results, leaking crankcase oil quite quickly.



Note: - - The pressure relief valve idea is a cheap possible pressure relief fix should the PCV path or orifice become blocked. However, the valve pictured and purchased from off Amazon, must have the springs replaced with a softer spring I obtained from Ace hardware and cut down to a shorter length. The valve has an adjustable knob on top and opening pressure must be set between 2 to 5 PSI.

Also, I would advise buying a new oil fill cap and using it for this purpose so that in the event you need to take the vehicle in for service, the cap could be changed back to factory original.
 

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Discussion Starter #46
By any chance, does anyone happen to know if gm fixed this issue on later models by enlarging the hole for the pcv? I will likely go the route of the pressure release for piece of mind - cheap reliable solution to something potentially catostrophic.

There has been no GM fix for the 2.4L PCV orifice issue that I am aware of as of this writing. Interestingly, the problem also is present on two versions of GMs 1.4L (and maybe 1.5L) engines as well. Although, those engines use a slightly different design, but results are the same. The PCV orifice gets clogged with carbon deposits or frozen with moisture in low double and single digit temperatures. Then the crankcase is pressurized with blow by gases and main seal damage results, leaking crankcase oil quite quickly.



Note: - - The pressure relief valve idea is a cheap possible pressure relief fix should the PCV path or orifice become blocked. However, the valve pictured and purchased from off Amazon, must have the springs replaced with a softer spring I obtained from Ace hardware and cut down to a shorter length. The valve has an adjustable knob on top and opening pressure must be set between 2 to 5 PSI.

Also, I would advise buying a new oil fill cap and using it for this purpose so that in the event you need to take the vehicle in for service, the cap could be changed back to factory original.
Question. Would venting the oilcap actually have any benefit as there is already a crankcase vent on top? If the issue lies in the bottom 'pcv' hole in the intake manifold, how would venting the top of the crankcase (which is already vented) add any 'protection'. I have noticed the vent tube (crankcase to intake) to freeze, any standing water would block that path, and that line does not seem to warm up at all (in cold weather water will freeze on top of the engine cover right next to that line. This is where I could see the oil cap vent being a benefit. I noticed last winter, a few rough startups, once I disconnected that vent tube, the rough start ups disappeared.

Not questioning your opinion or smarts, just trying to gain a little better understanding of the actual underlying problem. In my case it has been 100% in the vent tube. (Water freezing inside and not getting warm enogh to fully melt)
 

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I was wondering the same thing. As far as I know, that line is only an atmosphere vent to the valve cover. Didn't check if it has a check valve or anything, I'd think not.

Big question here being, since these engines are already recalled (for one factory at that) up to 2014, wouldn't it stand to reason that we will start seeing the same issue on every other 2.4 as the design hasn't been changed?
 

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I was wondering the same thing. As far as I know, that line is only an atmosphere vent to the valve cover. Didn't check if it has a check valve or anything, I'd think not.

Big question here being, since these engines are already recalled (for one factory at that) up to 2014, wouldn't it stand to reason that we will start seeing the same issue on every other 2.4 as the design hasn't been changed?
Question. Would venting the oilcap actually have any benefit as there is already a crankcase vent on top?


The idea for venting the oil fill cap with a pressure relief valve is for an additional path to provide crankcase pressure relief IF either the PCV or the fresh air line from the air plenum to the valve cover gets clogged or frozen. The oil cap is a larger diameter opening than either the PCV or fresh air line. Also higher up, larger surface are to warm up and remain free of both frozen water vapor or combustion product build up. Also, the oil fill cap is in an area that allows a more direct path to the crankcase . . . when you pour new oil in, it goes down into the crankcase. So likely to vent any pressure if something else is amiss.

At any rate, apparently the fresh air line from the air cleaner plenum did not prevent folks from experiencing main seal blow out. So hopefully a pressure relief valve would make for cheap insurance.


The fill cap pressure relief valve would mimic what older cars had. The "fill cap" was an open to air "oil breather" design that fit into a tube that ran into the housing top of the timing chain cover. Later, car makers started putting the oil fill cap on one of the valve covers in a V8.
Regarding freezing/clogging of the PCV and fresh air intake tube on +2014 models. . . This past winter with low double and single digit winter temps even in areas from New England as far down as the Carolinas and west, there was a rash of folks who had late model 2.4L engines freeze up (and blow main seals) due to short drives and moisture build up in the PCV. Quite a few came here to the forum and sounded their disappointment.
 

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It sounds like the best preventative measure would be to ensure at least some longer drives take place to burn out as much of the moisture as possible.
 

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It sounds like the best preventative measure would be to ensure at least some longer drives take place to burn out as much of the moisture as possible.

That certainly would help I think also. That said, for many people it doesn't seem to be practical for their shorter drives to work, many starts and stops. Also, there were quite a few members here from Canada with 2.4L engines who did have long daily drives and still had PCV freeze ups.

So I guess the question is, how much warm up and how much driving would remedy the problem?

The PCV freezing and clogging is a problem on 1.4L and possibly 1.5L engines as well it seems which are newer engine designs than the 2.4L The turbo engines have a more complex PCV path as well. Some other car makers have similar problems with this.
 

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The PCV freezing and clogging is a problem on 1.4L and possibly 1.5L engines as well it seems which are newer engine designs than the 2.4L The turbo engines have a more complex PCV path as well. Some other car makers have similar problems with this.

How can owners of the 1.5L be proactive to avoid a blown engine seal before it happens ?
 

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How can owners of the 1.5L be proactive to avoid a blown engine seal before it happens ?

Well, not sure, but if you head over to the Chevy Cruze or Malibu forums you may find more info as to whether the 1.5L has shown to be as problematic. The good news is, that unlike the 1.4L and 2.4L engine, the 1.5L reportedly has a replaceable external "fresh air" PCV valve. So you should to be able to easily inspect and/or clean/replace it.The Equinox has the PCV valve in the same location but may be a different p/n.

Here is a link to the PCV valve for a 2016 Chevy Malibu 1.5L which I believe may be similar to the Equinox 1.5L. https://www.carid.com/2016-chevy-malibu-pcv-breathers/?filter=1&sub-model[Liter][]=1.5L
You can also check over on the Chevy Cruze forum for info. I have not bookmarked any posts for that forum for awhile.

In cold winter weather, might be a good idea to check it occasionally for any build up.

I wasn't going to bring this up, but there is also another apparent problem, although does not seem to be widespread with the 1.5L. Too early to tell.
 

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Good morning everyone. Been watching this site for awhile and wanted to finally post here.

I have a 2011 with the 2.4 and obviously want to prevent anything like a blown rear main seal seeing as this is my only vehicle and that's a very costly repair.

You guys said a pressure relief valve in the oil cap would help in case the orfice ever did freeze up. I was just curious if these would do the trick.

One is set to just 1psi where the other is set to 5psi. Thanks for any help.
 

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Good morning everyone. Been watching this site for awhile and wanted to finally post here.

I have a 2011 with the 2.4 and obviously want to prevent anything like a blown rear main seal seeing as this is my only vehicle and that's a very costly repair.

You guys said a pressure relief valve in the oil cap would help in case the orfice ever did freeze up. I was just curious if these would do the trick.

One is set to just 1psi where the other is set to 5psi. Thanks for any help.

The pictures are not displaying. Not sure why.
I would think the 5 PSI would work . .. but if you want to be on the safe side, 1 PSI might be ok also.
 
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Not sure why they aren't either. Sorry about that.

If I did go this route, would the 1psi to too small of a pressure to work correctly or the engine should always be under vacuum anyways correct?
 

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Not sure why they aren't either. Sorry about that.

If I did go this route, would the 1psi to too small of a pressure to work correctly or the engine should always be under vacuum anyways correct?

Correct. the engine crankcase would normally be under somewhat of a vacuum relative to atmospheric pressure. Under very hard acceleration (wider throttle opening ) the crankcase may have a bit of positive pressure rather than vacuum.
 

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The dealership won't void your warranty if you put a pop-off valve on your oil filler cap. If you are worried, modify a new one and replace it with the non-modified one before yo take you vehicle to the dealership. If you don't do the pop-off valve, you risk blowing the rear mail seal. IMHO

Good Luck
 
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