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[5th Gen : 08+]: Turns over won't start

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Old Mar 4, 2020 | 08:20 AM
  #31  
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That could be a sign of a faulty PVC valve allowing blowby to mix with the oil and cause the build up of engine sludge.
 

Last edited by Mopar340; Mar 4, 2020 at 08:24 AM.
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Old Mar 4, 2020 | 09:36 AM
  #32  
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wouldn't the blowby be directed into the air filter, is there not a pcv tube to the filter housing
 
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Old Mar 4, 2020 | 10:19 AM
  #33  
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The pressure,blowby and moisture from the crankcase are drawn by vacuum from a tube connected to the PVC valve directly to the intake to be recirculated mixed with fuel and air mixture to be burned. This is the way it works with a good functioning PVC valve if the valve is faulty it could prevent proper vacuum from forming to properly vent the crankcase. There's a spring plunger in the valve that operates under different vacuum conditions such as engine idle or during acceleration and cruising conditions to allow proper venting of the crankcase at all times.
 
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Old Mar 4, 2020 | 03:18 PM
  #34  
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filtered air from the air filter box is drawn in to the crank case to replace the air sucked out by engine vacuum. if the pcv is plugged, faulty or is overcome by xs blowby, the sytem backs up into the air filter box.
 
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Old Mar 5, 2020 | 01:57 PM
  #35  
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Originally Posted by primem
filtered air from the air filter box is drawn in to the crank case to replace the air sucked out by engine vacuum. if the pcv is plugged, faulty or is overcome by xs blowby, the sytem backs up into the air filter box.
How do you figure while the crankcase is at a positive pressure while an engine is running. The negative pressure is create from the intake side of the engine. If the PVC valve is plugged it won't allow the crankcase pressure to ventilate out
 
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Old Mar 5, 2020 | 02:46 PM
  #36  
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the pcv system has more than one tube.
if the pressure can'T flow out the pcv valve due to a blockage the pressure has to go somewhere...since there is a fresh air line from the filter box connected to the crankcase (thru the other valve cover or pcv tube) it flows that way...bringing oil saturated vapour with it. if it couldn't vent someplace it would blow out all the oil seals.
 
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Old Mar 6, 2020 | 08:30 AM
  #37  
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No it doesn't unless your 3.6l pentastar is different than mine the PCV valve has one outlet only for a hose to hook up and that hose goes from the PCV valve directly into the air box. There's no other hoses that hook onto the hose that goes to PCV valve. There's only one PCV valve on an engine.
 

Last edited by Mopar340; Mar 6, 2020 at 08:32 AM.
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Old Mar 6, 2020 | 02:23 PM
  #38  
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Originally Posted by Mopar340
No it doesn't unless your 3.6l pentastar is different than mine the PCV valve has one outlet only for a hose to hook up and that hose goes from the PCV valve directly into the air box. There's no other hoses that hook onto the hose that goes to PCV valve. There's only one PCV valve on an engine.
The PCV tube shouldn’t be hooked into the air box - see drawing below from Dodge service info.

There’s only 1 PCV valve and tube but there are 2 tubes necessary for correct operation of the PCV system.

The PCV valve and tube route crankcase vapors to the intake manifold from the rear valve cover.

The crankcase ventilation tube (or CCV) is what hooks up to the air box and front valve cover. This is the inlet for clean, filtered air to flow through the crankcase and allow vacuum through the PCV valve to draw vapors into the manifold.

If the PCV gets clogged or flow is reduced due to sludge build up, the crankcase pressure has to go somewhere, so it will push back through the CCV and into the air box.


#1 is PCV tube. #2 is PCV valve.
 
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Old Mar 7, 2020 | 06:31 PM
  #39  
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Did you perform a compression test first of all? Your camshafts look in bad shape. There look worn and the rocker maybe shot too. If you are getting oil in the cylinder, it either leaking from the spark plug tubs or the oil rings on the pistons. I would recommend to install a long block and get a tube of 3 bond sealer. How is the transmission?
 
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Old Mar 8, 2020 | 01:45 PM
  #40  
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Originally Posted by master tech
Did you perform a compression test first of all? Your camshafts look in bad shape. There look worn and the rocker maybe shot too. If you are getting oil in the cylinder, it either leaking from the spark plug tubs or the oil rings on the pistons. I would recommend to install a long block and get a tube of 3 bond sealer. How is the transmission?
I’m confused with,
I would recommend to install a long block

could you explain please?

would this pcv effect the compression i am getting with the test? or are you saying that is what may have caused possibly the gasket going?


thanks for all the info

 
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