BCChevyZ71
Newbie
So I haven't seen anyone do a write up on this I will assume maybe it hasn't been done yet. My 98 k1500 when I got it was very poorly maintained amongst the list of things that didn't get any love was the PCV system. I replaced the boots and grommets and the PCV valve itself and while consistently pulling apart the intake system and cleaning years of neglect. I noticed oil in the intake tract which I personally am not a huge fan of though its common at least in many trucks I've owned. I tried fram, ac delco, and other brands of PCV valves my local parts store offers for ***** and giggles. While in my searches on the interwebs I found a write up from the NBS 5.3 guys a hidden gem in a GM re call service bulletin about the LS 5.3 trucks using a similar PCV valve as the 5.7 vortec and seeing oil usage through the PCV system via the intake. The fix? A fixed orifice PCV valve no more spring .etc I sent my local parts house on a wild goose hunt to find me one......I have since lost the part number but one could search up the service bulletin and cross reference part numbers as I did. Long story short upon switching to the fixed orifice not only do I no longer see traces of oil on my intake but I firmly believe the PCV system is working far far far better then it ever did with an OEM style PCV valve. As well I will never have to replace my PCV valve again because it's no longer containing any moving parts springs .etc I can pull it off clean it with brake clean dry it out and re install. I couldn't tell you why it works so much better but I can tell you that since switching the pcv i still haven't developed any blow by or any kind of negative adverse anything and i have a perfect just enough Suction to hold a dollar bill to the oil fill tube while running. 302,000 km and I no longer have oil in the intake at least that I notice and for the 10 ish dollars it cost me its my favorite and best bang for my buck mod I've ever done on my truck.
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