PCV issue

88_AHB

88_AHB

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Hey all,
My pcv was making a odd noise lately like a chattering noise that's intermittent. Replaced it with a new pcv valve, still makes the same noise. Would this perhaps be consistent of a vacuum leak or something coming from the port off of the carb to make this noise? I could try and get a clip of the noise that it is making. The motor seems to run fine otherwise at idle and driving speeds.
 
What brand pcv are you using? I had problems with some aftermarket ones. Maybe find a mopar one if you can.
 
I got it from o'reilys i believe a fram or wix? Can't honestly remember.
 
Check the hose and port to make sure there's nothing starting to build up in them.
 
I'll check and see,the motor and carb etc. is practically new/rebuilt. Sounds like the check valve or whatever in the pcv chatters bad.
 
I've had metal ones that make noise and it's normal for the so called sliding pintle inside to make some noise so I wouldn't worry
 
What's your idle-vavuum.
The PCV has 4 modes of operation;
1) minimum flow at idle, where the idle vacuum is supposed to suck the valve to minimum-flow position.
2) Maximum flow, where the loss of manifold vacuum allows a little spring in there to push the valve open.
3) Variable flow in all positions where the calibrated spring and manifold vacuum argue about where the valve should be at every varying amount of vacuum. and
4) the slammed shut position, put there by a a sudden pressure spike in the intake, like a backfire.

If you have a very low manifold vacuum, like caused by;
a big cam,
or retarded ignition timing,
or a vacuum leak, etc;
then the PCV can be operating in the #3 mode at idle instead of #1 mode, which is often accompanied by a rattle. The calibrated spring inside it is calibrated very weak,lol.
 
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I haven't measured for vacuum yet I should and do need to. Last time I checked timing was where it should be. It does have a roller cam in it but nothing huge. I haven't noticed any sort of vacuum leaks that I'm aware of.
 
Does your car have any lope at idle, from the cam specs? Nothing to do with roller cam. If it does have even a little lope at idle, I bet it's enough for you to get some noise from your pcv valve. Probably intermittent.
 
Never had noise from a mopar pcv valve even with a lopey cam. It is the aftermarket fits all ones that cause the problems. Get a mopar one and I bet you won`t have any noise. If you vacuum was super low then the brake booster wouldn`t be working well either.
 
Long long time ago I picked up about 5 of these (3671076), I then went to the adjustable kind so that I could really tune that thing in (but that's due to the bigger cam, etc.).

Anyways, if you want, send me your address, I'll figure out the shipping (which is going to be your sole cost) and will send one your way (assuming you want one and can't get one locally any quicker...LOL).
 
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