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3.6 passes a lot of oil through the PCV system. Catch can on mine catches several ounces of oil and now I just disconnected the air intake for that system from the air box connection as I found oil in resonator box it connects to. Just using a small breather filer to clean PCV intake air. Next oil change I'll see how it is doing.
Well you can't sub in a breather filter for the PCV fresh air inlet hose that goes to the throttle inlet tube. Seems diameter of the tube on the inlet tube connection meters some of the inlet air. Got a lean LTFT code and a CEL after a few weeks. Watched the STFT move around too much, system will trigger code if trims go more than minus or plus 10 on the fuel trims. Watched it live on my scan tool. So PCV inlet air is back onto the intake tube, catch can has no effect on fuel trims though. Reason for that mod was seeing a little oil in the intake tube ''catch reservoir''.
 

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Discussion Starter #42
Interesting how you got those codes I'm guessing the blow by that comes out of the crankcase actually gets counted in the exhaust stream from the upstream 02? U plugged the intake tube but had a breather on the valve cover? I'm like how could the computer pick that up? Interesting
 

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2013 2.4 was burning about 1 quart/2000 miles. Dealer won't do squat for it, says neither the clogged PCV breather TSB nor the piston ring service applies, even though we have the letter with our VIN saying we're eligible for the piston ring service if we have oil consumption issues. Dealer thought it was a clogged PCV, but wanted $600 to clean it. I did it myself and the PCV was not clogged.

On a whim, I tried a can of BG EPR 109 that's good for freeing up stuck rings. Certainly must have unloaded a lot of crud, the clean oil was black as ink after running for 15 minutes. Gave it another oil change, and 1000 miles later, the oil level hasn't changed. Maybe it was sticky rings and it helped.
 

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Discussion Starter #44
Rings do get dirty prior to rebuilding I've sprayed brake cleaner/gumout. spray into the spark plug holes as I changed the oil. It burned alot less oil...i rebuilt the motor with the engine in the car because of a sloppy timing chain. When I pulled the head there was carbon the size of golf balls on all the valves. Yea if chevy does rebuild it they don't actually rebuild the Motor they re use EVERYTHING and only replace the rings with factory spec so people have had the problem return.... When I did rebuild I found a cracked piston. But yea if chevy does do something for you even it won't be right anyhow. What a joke they charge 7500 to do THAT.
 

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Interesting how you got those codes I'm guessing the blow by that comes out of the crankcase actually gets counted in the exhaust stream from the upstream 02? U plugged the intake tube but had a breather on the valve cover? I'm like how could the computer pick that up? Interesting
Had a breather filter on the clean air intake hose that goes to front valve cover. 3.6 motor. O2 sensor adjusts fuel mixtures so it sensed too much unregulated air going into intake manifold via the PCV that connects directly to the intake manifold. When PCM has to add more fuel than it's map dictates at idle it sets a lean code, same result would be from a vacuum leak also.
Vacuum side of PCV only passes a set amount of air, excess blow by will go back up the fresh air intake side of the PCV system as it's wide open, no restriction, when I saw some oil in the intake tube I was trying to eliminate that from happening by disconnecting it and just running a separate filter on the fresh air inlet.
 
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Just completed a 4200mi road trip Houston-Orlando-Beech Mountain NC-Nashville-Houston with my oil blend. The engine barely use any oil at all. First time in 10 yrs to put the tranmission to M to drive to the top of Grandfather Mountain (1mi high) and Beech Mountain, some scary turns.The car started fine at 25F in the snow at the top of Beech Mountain. Half way into the trip I changed both solenoids while in Orlando because of some rattle during startup. It cured the noise. Strange that these solenoids were replaced about 35k mi ago. It was an easy 15 min job anyway. Will continue to increase the blend to 50-50 of 5W-30 and 5W-40.
 
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