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Discussion Starter #21

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Welp someone who sees this from my view, good to know I could be looking in the right direction with this.
So far, everything smooth with a breather.

Yes. . but what is the engine fuel trim now? Do you have an OBDII to monitor thator any other engine operating parameters? If no code get logged and therfore no CEL, it could be running rich and eventually trash the catalytic converter.

Better to be scientific about it than willy nilly change things.
 

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Discussion Starter #23
Welp someone who sees this from my view, good to know I could be looking in the right direction with this.
So far, everything smooth with a breather.

Yes. . but what is the engine fuel trim now? Do you have an OBDII to monitor thator any other engine operating parameters? If no code get logged and therfore no CEL, it could be running rich and eventually trash the catalytic converter.

Better to be scientific about it than willy nilly change things.
I do have a scanner, periodically have been checking. Short background on my end, I have been working on cars for +15yrs. Does not make me an expert mechanic. I refuse to go into something that will make an issue worse, or create a different problem. I despise hack jobs.

Short end on this; In cold climates with my my car. As of today, any levels I see as important are normal. I currently have no moisture or residue under the oil cap, no frozen line at the valve cover. Only time will tell at this point. In the summer months I may have different results and am looking into potential issues. Running rich would be caused from the hole in the intake (that hole is currently sealed, all air into intake is monitored via maf, I do not expect to see an issue, if for some reason i do, I can revert back to factory)
 

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As I understand it +20% fuel trim means the PCM is compensating by adding fuel. That would make sense as the MAF is seeing less air flow than normal ( due to the hose being off the air box ) and therefore the PCM 's programming would deliver less fuel. The engine is not really running rich, the O2 sensor is telling the PCM that it is seeing a lean mixture and the PCM is adjusting the fuel trim to correct it. Plugging the opening that the hose connects to should return the fuel trim to near normal.
 

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Discussion Starter #25
I see, but that line does not route air FROM the crankcase into the air box, but supplies fresh filter air from the air box into the valve cover area and into the engine.
The air then circulates into the crank case and is sucked into the intake manifold via the tiny hole (PCV orifice) that gets drilled out as shown in the TSB.

That tiny hole is what usually get clogged with both oil/carbon deposits and water vapor in winter. . . when it will freeze and cause pressure to build up in the crankcase which then will blow out the rear main seal.

If the idea is to try to remedy any crankcase pressure IF the PCV orifice freezes or gets clogged, then a pressure relief "fail safe" valve might be a better choice. That way, even if the intake air line or PCV orifice gets clogged/frozen .. . crankcase pressure can be released and not damage the main seal. When the engine gets warm enough, any water will melt and the system will return to normal operation - - - meaning a slight vacuum in the crankcase rather then pressure because of a clogged PCV path.
The line that connects the valve cover and air intake, on the 2.4 and many others, it is used to aid in removing gases from the crankcase. The intake pulls in fresh air from the air filter as well as from the crankcase. The connection is there to create a more emission friendly motor. The gasses are pulled back through the intake, burned again, passed through the cat and out the exhaust. An issue with gdi is that more condensation (moisture) is created. That moisture is pulled back through (with blow by and burps of oil) to the intake, passes by the intake valves and sticks to them along the way. Excess moisture is really only seen in cold climates, less than 20 degrees. By eliminating this line, it is a felony as it has to due with emissions (removing that line releases gases into the atmosphere) by adding a catch can, it will collect, not all, but some of the water and gunk from inside the valve cover.
Cars from 'back then' simply had a line ran from the valve cover to the the bottom of the car to vent, thus releasing the gasses into the atmosphere. The pcv was created as a way to trap theses gasses and pass them through the cat. Unfortunately for the gdi, it is impending doom for the valves.
 

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The line that connects the valve cover and air intake, on the 2.4 and many others, it is used to aid in removing gases from the crankcase. The intake pulls in fresh air from the air filter as well as from the crankcase. The connection is there to create a more emission friendly motor. The gasses are pulled back through the intake, burned again, passed through the cat and out the exhaust. An issue with gdi is that more condensation (moisture) is created. That moisture is pulled back through (with blow by and burps of oil) to the intake, passes by the intake valves and sticks to them along the way. Excess moisture is really only seen in cold climates, less than 20 degrees. By eliminating this line, it is a felony as it has to due with emissions (removing that line releases gases into the atmosphere) by adding a catch can, it will collect, not all, but some of the water and gunk from inside the valve cover.
Cars from 'back then' simply had a line ran from the valve cover to the the bottom of the car to vent, thus releasing the gasses into the atmosphere. The pcv was created as a way to trap theses gasses and pass them through the cat. Unfortunately for the gdi, it is impending doom for the valves.
Oh my, apologies if you got confused.

Cars "from back then" also often had a vented oil filter cap. Later, a PCV valve was added to a valve cover with a vacuum line usually connected to the base of the carburetor.

Yes. .. I have worked on my cars (and others) for many years and owned some 38 at this point . . including cars with carbs and early PCV systems that had actual valve cover PCV valves.
I also know that the line you speak of is a "fresh air" line that should have a filtered air supply and how the 2.4L PCV system functions.
I also understand the EPA reasons for the OEM connections to that air line.
Think about it. Without that air INLET line ( towards the engine block), it would be a closed system and the PCV intake manifold orifice would have no way to maintain an air flow.
Those "burps" you speak of in that air line and resulting oil/water emulsion deposits are part of the normal engine firing pulsations such as you felt at the end of the line when you removed it at idle. Under more open throttle running conditions, there should be a fairly slight vacuum on that line allowing filtered and MAF metered air into the inside of the engine. From there, the idea is for the air to ventilate and work it's way to the the small PCV orifice where it is drawn into the intake manifold. That small PCV orifice is the usual root of the problem getting clogged with both oil sludge and frozen water vapor in cold weather. . . . not the air line you are worried about. But if adding a breather makes you feel better and it does not trigger DTCs, have at it.

Again. . that air line you removed is not meant to be a vent to let crankcase vapors "out". . . it is an air inlet to allow filtered air into the crankcase. You have it backwards. The PCV orifice is in the cylinder head and draws crankcase vapors into the intake manifold burning them up as the engine runs, thus satisfying the EPA mandates of not allowing blow by gases into the atmosphere. Some backflow "burps" are normal but not the bulk of PCV vapor flow.

Most newer car and truck engines today are like this, having an internal PCV vapor path in the cylinder head somewhere and an orifice that allows crankcase vapors to be drawn into the intake manifold. . not through the throttle body. It just so happens there may be residual back flow of vapors under idle and certain other conditions.

Don't know why you think you need to explain that to me, but others may like to know.
 

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- - - (with blow by and burps of oil) to the intake, passes by the intake valves and sticks to them along the way.

One more thought . . . if you are getting more than usual of these "burps" on that air line, it may be a sign that you have more blow by than normal indicating worn pistons rings.
Given that it is a 2.4L GDI engine and the TSB regarding this, you may want to do a compression check on all cylinders.

Excessive blow by would cause more oil/water in the air line.
 

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Discussion Starter #28
- - - (with blow by and burps of oil) to the intake, passes by the intake valves and sticks to them along the way.

One more thought . . . if you are getting more than usual of these "burps" on that air line, it may be a sign that you have more blow by than normal indicating worn pistons rings.
Given that it is a 2.4L GDI engine and the TSB regarding this, you may want to do a compression check on all cylinders.

Excessive blow by would cause more oil/water in the air line.
Def no arguments, just trying to get a common middle ground, tons of info back and forth on the issue.
I'll try to clarify a few questions, concerns on my end and again big thanks for your input much appreciated.
1) The 2.4 has a pcv built into the motor, this would be vented inside intake manifold (the tiny hole that can freeze)
2) the valve cover is not the pcv side, but rather an orifice to prevent pressure build up in the valve cover
3) since the valve cover is not the pcv valve, a traditional catch can cannot be utilized. However, when there is positive pressure in the valve cover, it will push air out through the line into the air intake (connection above the motor) The intake assists in removal of this pressure (which will also draw out gasses and more importantly in this case, the excess moisture created in cold climates, such as mine this time of year) the catch can would contain the water and prevent it from entering the intake.
4) the idea of pcv is of course to relieve pressure. For epa standing it lowers emissions by allowing the motor to burn up these gasses. The bad thing for gdi is that these gasses pass over the valves and cokes them. I'm not as concerned about the gasses, again I'm more concerned with the water (moisture, condensation) that is built up in the valve cover and being ejected into the intake from the valve cover. This excess moisture is only present in cold climates, I typically see an excess when it is sub 20. I'm sure if my car was left in a garage overnight I would not have as big of a problem with this, but being left outside increases the condensation. I have about a 20 min drive to work, I'll typically start my car a few mins before I leave, so my car might be running 30 mins in total on my commute if I'm lucky.
5) lastly, is there a write up on the removal of the intake manifold? I read through one, it said the fuel pump had to be disconnected. It also said the a.c. had to be removed. I haven't looked too far into it, it's been too cold here in Ohio recently. Another confusing topic, sounds like Something that is recommended to check, but to evacuate the a.c. is not a simple task and i would not want to open it up.
 

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I do not know of a really good write up for the 2.4L intake manifold removal.

There may have been one or two dealing with it on the forum. Best to try a GM or Helm manual or one of the online service manual assists.

Member Bigb1259 is a repair guy and might post or steer you on to the right info.
 

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Hey Tankmalone,
I am also looking at the 2.4's PCV system with a view towards installing a catch can. In my opinion the hose between the air box and the valve cover is bi-directional, meaning under some conditions ( high intake vacuum ) the flow direction will be clean air into the valve cover and under other conditions ( low intake vacuum ) the flow direction will be crankcase gases out into the air box. Adding a catch can into this line is not ideal but certainly would help catch some oil and moisture. ( high mileage engines with alot of blow-by would benefit more ) Here are a few thoughts on this... 1) Keep all hose runs as short as possible - use hose materials that will minimize heat loss 2) Route all hoses downward so that liquids will drain back into the catch can with no low spots for liquids to accumulate and freeze 3) Don't use any kind of fine mesh filter in the system - they will quickly freeze up. 4) If the catch can has a dip tube be sure that it doesn't extend down too far to avoid contact with any liquids 5) In winter add a small amount of antifreeze/water mixture 70/30 into the bottom of the catch can to prevent the liquids from freezing. (repeat after emptying) 6) Most importantly empty the catch can often. If you do decide to install a catch can, please post your results.
 

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Discussion Starter #31
Hey Tankmalone,
I am also looking at the 2.4's PCV system with a view towards installing a catch can. In my opinion the hose between the air box and the valve cover is bi-directional, meaning under some conditions ( high intake vacuum ) the flow direction will be clean air into the valve cover and under other conditions ( low intake vacuum ) the flow direction will be crankcase gases out into the air box. Adding a catch can into this line is not ideal but certainly would help catch some oil and moisture. ( high mileage engines with alot of blow-by would benefit more ) Here are a few thoughts on this... 1) Keep all hose runs as short as possible - use hose materials that will minimize heat loss 2) Route all hoses downward so that liquids will drain back into the catch can with no low spots for liquids to accumulate and freeze 3) Don't use any kind of fine mesh filter in the system - they will quickly freeze up. 4) If the catch can has a dip tube be sure that it doesn't extend down too far to avoid contact with any liquids 5) In winter add a small amount of antifreeze/water mixture 70/30 into the bottom of the catch can to prevent the liquids from freezing. (repeat after emptying) 6) Most importantly empty the catch can often. If you do decide to install a catch can, please post your results.
Do you have shorter trips in cold weather?
Of course, Ideally I'd like to leave it stock. My plan is hopefully get it finished today (good freezing rain right now and I don't have access to a garage) once the weather warms up I will compare what is collected in the catch can. My guess is, in the warmer months the catch can will not be needed as there should be less condensation in the motor.
 

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Hey Tankmalone,
I am also looking at the 2.4's PCV system with a view towards installing a catch can. In my opinion the hose between the air box and the valve cover is bi-directional, meaning under some conditions ( high intake vacuum ) the flow direction will be clean air into the valve cover and under other conditions ( low intake vacuum ) the flow direction will be crankcase gases out into the air box. Adding a catch can into this line is not ideal but certainly would help catch some oil and moisture. ( high mileage engines with alot of blow-by would benefit more ) Here are a few thoughts on this... 1) Keep all hose runs as short as possible - use hose materials that will minimize heat loss 2) Route all hoses downward so that liquids will drain back into the catch can with no low spots for liquids to accumulate and freeze 3) Don't use any kind of fine mesh filter in the system - they will quickly freeze up. 4) If the catch can has a dip tube be sure that it doesn't extend down too far to avoid contact with any liquids 5) In winter add a small amount of antifreeze/water mixture 70/30 into the bottom of the catch can to prevent the liquids from freezing. (repeat after emptying) 6) Most importantly empty the catch can often. If you do decide to install a catch can, please post your results.
Yes, as was discussed, that hose can be bi directional especially with little vacuum at idle and some other conditions. And, as i stated earlier, a few posts back, if the piston rings are worn there will tend to be more blowby so more water and oil vapor in that line.
So it could be an indication that the engine is showing signs of the early piston ring wear as detailed in the TSB regarding this and a few other things.

In my opinion, adding a catch can in the air box line will do little to remedy any issue of moisture/carbon build up and potential freezing in the PCV orifice which is buried inside the intake manifold.

As a side note, in previous non DI 2.4L engines there was little to no moisture present in the same line to the air box. I just worked on a 2009 Saturn Aura with 2.4L engine and it had very slight oil filming, but no moisture in the line at all and no yellow oil water emulsion.


https://www-odi.nhtsa.dot.gov/acms/cs/jaxrs/download/doc/UCM507373/SB-10057259-1717.pdf

https://gm.oemdtc.com/3953/15285-excessive-engine-oil-consumption-2011-chevrolet-equinox-gmc-terrain
 

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Discussion Starter #33
Hey Tankmalone,
I am also looking at the 2.4's PCV system with a view towards installing a catch can. In my opinion the hose between the air box and the valve cover is bi-directional, meaning under some conditions ( high intake vacuum ) the flow direction will be clean air into the valve cover and under other conditions ( low intake vacuum ) the flow direction will be crankcase gases out into the air box. Adding a catch can into this line is not ideal but certainly would help catch some oil and moisture. ( high mileage engines with alot of blow-by would benefit more ) Here are a few thoughts on this... 1) Keep all hose runs as short as possible - use hose materials that will minimize heat loss 2) Route all hoses downward so that liquids will drain back into the catch can with no low spots for liquids to accumulate and freeze 3) Don't use any kind of fine mesh filter in the system - they will quickly freeze up. 4) If the catch can has a dip tube be sure that it doesn't extend down too far to avoid contact with any liquids 5) In winter add a small amount of antifreeze/water mixture 70/30 into the bottom of the catch can to prevent the liquids from freezing. (repeat after emptying) 6) Most importantly empty the catch can often. If you do decide to install a catch can, please post your results.
Yes, as was discussed, that hose can be bi directional especially with little vacuum at idle and some other conditions. And, as i stated earlier, a few posts back, if the piston rings are worn there will tend to be more blowby so more water and oil vapor in that line.
So it could be an indication that the engine is showing signs of the early piston ring wear as detailed in the TSB regarding this and a few other things.

In my opinion, adding a catch can in the air box line will do little to remedy any issue of moisture/carbon build up and potential freezing in the PCV orifice which is buried inside the intake manifold.

As a side note, in previous non DI 2.4L engines there was little to no moisture present in the same line to the air box. I just worked on a 2009 Saturn Aura with 2.4L engine and it had very slight oil filming, but no moisture in the line at all and no yellow oil water emulsion.


https://www-odi.nhtsa.dot.gov/acms/cs/jaxrs/download/doc/UCM507373/SB-10057259-1717.pdf

https://gm.oemdtc.com/3953/15285-excessive-engine-oil-consumption-2011-chevrolet-equinox-gmc-terrain
Could be a bigger issue, but blow by is common in all gdi. Blow by has been linked to coked valves. Do I have an increase in blow by, not sure, last oil change I had 5qts drain out at 4.5k miles so no signs of oil consumption, no signs of excessive blow by. Again this is related to excess moisture in cold climates especially with short trips. That is all im trying to solve, i know there could in theory be another reason. however, everything is operating as it should. The Engine does not come up to temp to burn off excess moisture, more water vapor is present in a gdi, not so much an issue with non gdi. If I had a longer commute to work I would not be having this issue. I could drive out of my way and down the highway to burn off the excess moisture, but that's not practical in my case. I shouldn't have to drive my car, put on extra miles, spend more on fuel, and use more of my time to keep this motor in top shape in the winter. Terrible design and all car manufacturers know it. Gm is already starting to implement catch cans in line, not to catch oil, but to catch excess moisture. In a few days I'll post what drains out of the catch can and thankfully it will not end up in the intake.
I know the engines are different, but they operate on the same principles. I've looked into lsx issues, there is more info on those due to cult following. Most of these issues are all related to condensation not being able to boil off.
 

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Discussion Starter #34
I should also be asking opinions on the pcv freezing over. To me, again with cold climate short commute blah blah....with this moisture staying within the system, it can not be good, as it is the valve that freezes over that causes this issue. (Oil seal blow out and excessive blow by) So by finding a way to keep the moisture out of the system, it would drastically reduce the chance of anything freezing over, correct?
 

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Could be a bigger issue, but blow by is common in all gdi. Blow by has been linked to coked valves. In a few days I'll post what drains out of the catch can and thankfully it will not end up in the intake.
I know the engines are different, but they operate on the same principles. I've looked into lsx issues, there is more info on those due to cult following. Most of these issues are all related to condensation not being able to boil off.

I understand. But a catch can on the intake air line will not remedy the majority of the water and oil vapor passed directly into the intake manifold by the internal PCV orifice.

And as stated over and over in many other threads, yes, cold and even just humid rainy weather cause more engine moisture build up in the crankcase.
I have installed a true PCV catch (Elite Catch Can) can on my 2015 LFX 3.L V6. I installed it on the third day I owned the 2015 Equinox and empty it regularly.

On that engine, the PCV orifice is pressed into the top of the rear valve cover and routed to a fitting via a tube directly to the intake manifold. There is also a "clean" air line such as you are concerned about, but I can attest to the fact that the "dirty" flow from the PCV orifice flow many times more the water/oil vapor to the intake manifold and valves than that "clean" air line as it is called.

And, really, it isn't so much the water vapor that causes the intake valve coking, but the oil mist, vapor and blow by contaminants that the PCV orifice passes.
 

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I should also be asking opinions on the pcv freezing over. To me, again with cold climate short commute blah blah....with this moisture staying within the system, it can not be good, as it is the valve that freezes over that causes this issue. (Oil seal blow out and excessive blow by) So by finding a way to keep the moisture out of the system, it would drastically reduce the chance of anything freezing over, correct?
Lot's of threads here about the PCV orifice freezing. Check them out by doing a google search for them rather than the search box here. It is not a "valve" by the way. GM sizes an orifice to control the amount of flow through this orifice. It no longer has a ball type check valve in this engine nor the 3.6L LFX V6.
There is a small, internal cylinder head ball type PCV valve in the GM 1.4L turbo engines used in Chevy Trax, Buick Encore and Chevy 1.4L turbo Sonics. These also have chronic freezing and clogging due to crankcase vapor deposits.
 

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Do you have shorter trips in cold weather?
Of course, Ideally I'd like to leave it stock. My plan is hopefully get it finished today (good freezing rain right now and I don't have access to a garage) once the weather warms up I will compare what is collected in the catch can. My guess is, in the warmer months the catch can will not be needed as there should be less condensation in the motor.
Hey Tankmalone,
No most of my driving is 30 minutes or less with tempertures +10F to -15F range. And its frequently parked in a heated garage overnight. My 2017 has only 38,000Km so not much blow-by yet. I have to agree that the catch can may not be needed in warmer weather, but once installed I'm planning to leave it in all year round. I was hoping install one in March or April as I'm currently working 6 days a week.
 

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Hey Tankmalone,
No most of my driving is 30 minutes or less with tempertures +10F to -15F range. And its frequently parked in a heated garage overnight. My 2017 has only 38,000Km so not much blow-by yet. I have to agree that the catch can may not be needed in warmer weather, but once installed I'm planning to leave it in all year round. I was hoping install one in March or April as I'm currently working 6 days a week.

Pardon. .. but all you both are discussing is information that is already known and posted in quite a few threads here.
Yes, , more will collect in a catch can in cold or humid weather. I have had one on my Equinox for 3 years. I live and drive in single digit temps and minus single and double digits. .

If you really are interested in what has come before regarding this then use google to search. . Google>Equinoxforum>oil catch can

Also, if both of you are really interested in doing something preventative, I would to the following.

For winter use, buy another oil fill cap. Drill a hole into it and install a low pressure relief valve into it. That way, should the PCV orifice (not valve - - there is no valve)
freeze, then any crankcase pressure would not blow out a main seal.

Something like this - - -



 

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Discussion Starter #39
Hey Tankmalone,
No most of my driving is 30 minutes or less with tempertures +10F to -15F range. And its frequently parked in a heated garage overnight. My 2017 has only 38,000Km so not much blow-by yet. I have to agree that the catch can may not be needed in warmer weather, but once installed I'm planning to leave it in all year round. I was hoping install one in March or April as I'm currently working 6 days a week.

Pardon. .. but all you both are discussing is information that is already known and posted in quite a few threads here.
Yes, , more will collect in a catch can in cold or humid weather. I have had one on my Equinox for 3 years. I live and drive in single digit temps and minus single and double digits. .

If you really are interested in what has come before regarding this then use google to search. . Google>Equinoxforum>oil catch can

Also, if both of you are really interested in doing something preventative, I would to the following.

For winter use, buy another oil fill cap. Drill a hole into it and install a low pressure relief valve into it. That way, should the PCV orifice (not valve - - there is no valve)
freeze, then any crankcase pressure would not blow out a main seal.

Something like this - - -



What motor do you have?
Reading from you that a catch can will collect more in the colder climates is moving forward. I'm not expecting it to be a one stop cure for all issues, that just won't happen.
Lots of info here and other places on the topic. however unfortunately on this site, there does not seem to be sufficient traffic for such topics to be discussed in depth. I'm not looking into getting into a fit about who's smarter than the rest, it's not my intent. It's about solving a problem, even if its just a minor preventative. Adding a pressure valve to the top of the oil cap would be a solid pick up. I started thread this to begin a fresh run down on opinions and what others have done, seen, and experienced.
 

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I already stated what motor I have and is shown below in my signature. so seems things are getting ignored or glossed over.
Ok. . just trying to help. It's just that this same scenario of questions, ponderings, findings, etc so much is really already in earlier threads here. If you have read through existing threads, it is often helpful and it has been stated in those threads that yes, more is collected in cold or humid weather so nothing fresh or new about that either.
Also, I provided the same information regarding the PCV orifice, path and pressure relief valve earlier in this thread in posts #4 and #6 , but seems it was ignored.

So just trying to help by indicating first hand experience myself since I have worked on these 2.4L engines as well and the 3.6L V6 which has it's own similar. PCV issues. I do not recall indicating it's anything about who is smarter. But it seems any help isn't really appreciated or ignored. I see errors in terminology and some misunderstanding about this PCV system in this discussion so tried to point them out.

There is less posting traffic here since software change last year which in some ways is less user friendly. Not likely to get a lot more new information on the PCV subject so all the more reason to search out what is already here.

So standing by. . have a good night and good week.
 
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