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Too Low of idle cause PCV to malfunction ?

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Jer

Jer

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My 67 has the original "pancake" style pcv valve installed, I originally had issues when I first purchased the car years ago & it turned out that the DPO had removed the spring from inside when installing a new diaphram... so I ordered a whole new unit & it has been working just fine since (no more smoking out a city block..) This season at random times it has started smoking on me always when stopped at a light (& clears up right away after taking off), not every time but when it happens it is when I'm stopped at a light, this weekend I was out for a last ride of season (making sure the fuel stabilzer is all the way thru, there was no smoking issues, then I realized I still had the choke on part way (higher idle) so I took choke off all the way & it went down to low idle, next stop sign, it smoked on me... started thinking, this season I have had the idle lower than normal (because I liked the sound of the low idle :smile: - kinda Harley'ish) - I wonder if it's possible with a really low idle that the vacuum is to high for the pcv valve & causes it to act up ? just throwing the idea out there, not sure if others have noted this before, I know I can always order a new pcv valve or retro fit one from a nissan sentra (I think) etc. But wanted thoughts on having the idle to low causing issues with PCV valve... Obviously next season I will bump up the idle & see but thought someone would know for sure & save me 5 months of waiting - I have the idle so low you swear it would stall but it doesn't ;-)
 
Looks like all the old posts/replies to this are now gone. I would consider narrowing the tube from the pancake PCV to the intake manifold so-as to lessen the vacuum.

It was embarrassing the time my Sprite gulped a fair bit of oil through the pancake. I had a lady honking at me as if I was on fire... and, frankly, it looked like I was (given the billowing smoke). It took a few miles to thin it all out (to a light blue and then gone). As BillM posted (but was deleted in the software change-over), maybe a 9/64" tube or orifice will dial it down a bit (and I know Gerard has written as much). In my own case, the 1275 would occasional let a little oil by in the first mile or two of driving (cold) but it would go away. Still haven't resolved it (short of plugging up the vacuum intake port and plugging up the hose to the oil separator). I figure I'll try to dial it down (or just not create any PCV).
 
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