2003 Suburban PCV Valve - Nothing In It?

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Mar 17, 2011
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Location
Florida
2003 Suburban 1500 5.3L Vortec.
Decided to change my PCV valve, but I heard that somewhere around my year, they went with a PCV system in the valve cover.
When I took mine out, there was a grommet in the valve cover and what looks to be a PCV valve body with a very small hole on the valve cover side of the PCV body, but there is nothing in it.
At first, I was concerned, but then I saw a video where someone had the same issue, but couldn't explain why it was like that and ended up swapping it for a conventional PCV valve.
Can anyone explain what is happening with this "dummy" valve? Is the valve cover PCV system in this model and this is just a pathway for the gasses? Not sure what to do with replacement to tune up the PCV system.
 
They decided a fixed orifice was good enough under all conditions.

The point of a PCV valve is to be open most of the time, but spring closed at idle so as to not be a huge vacuum leak.
 
Does the 03 require any sort of PCV maintenance? Did this one have the PCV built in the valve cover, or just a fixed orifice PCV fitting?
I have started to develop a small rear main seal leak and wanted to rule out PCV issues as a contributing factor...also as general maintenance, I am used to changing PCV valves.
 
No maintenance other than visual inspection to make sure the orifice is clear. You can run the updated Gen IV/GMT900 left valve cover (P/N 12570427) if you want as the PCV Grommet in the early Gen III valve covers harden over time making the PCV system less affective.
You will need a short piece of piece of 3/8" Transmission Oil Cooler Hose to connect the original plastic PCV line to the Valve Cover.
This eliminates the PCV Valve altogether as the orifice is built into the Valve Cover.

It's not the Rear Main Seal that leaks....But the rear Engine Cover Gasket. Of coarse you do the rear main at the same time....But be sure to change the Cover Gasket while the Trans is out!
 
That's normal. A standard PCV, for some reason, increases oil consumption on those engines. I swapped the PCV in my '02 for an '03 and later open orifice style and put a 3 psi check valve on the inlet side to draw a slight constant vacuum on the crankcase at idle and cruise.
 
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