dsteelejr

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Ya, I remember that thread what a nightmare. I remember one of the guys trying to tell me GM put the PCV valve in the wrong side of my engine (I have stock tin covers). And then there was someone that thought running 2 PCV valves was a good idea, shesh.

:wtf2::roflbow::rotflmao:
 

AuroraGirl

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8psi is way too much for an edelbrock. Take a look down the primaries while its running and see if you are getting fuel dripping into the throat. Do you have a wideband or other way to tune the carb? They are usable out of the box usually, which is why people like them. But they will almost always need to be fine tuned for the application to get the best performance. They are almost always pretty rich all the way through the operating range. I bet if you pull a plug it will be covered in carbon from being excessively rich.
this is a personal attack
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I havent pulled them lately but this is what they originally looked like when I first did plugs on my truck. If i pull them now, they wont be so wet and oily, more just carbon and black.
I have a 1406 and for a long while it ran rather retarded as well, in addition to my more fouling-prone use of the truck. But A pricy but convenient way to deal with the psi issue is a edelbrock brand pump which regulates to the proper psi according to them. pricy tho.
 

AuroraGirl

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Ya, I remember that thread what a nightmare. I remember one of the guys trying to tell me GM put the PCV valve in the wrong side of my engine (I have stock tin covers). And then there was someone that thought running 2 PCV valves was a good idea, shesh.

It sound like you know you need to run PCV valve. Good. A couple options I can think of. #1. post a video of it both with the PCV valve and with it plugged off. #2. Try a different brand of PCV valve, sometimes manufactures have a bad batch of parts sent out without knowing it, especially these days where that valve was made who knows where and subject to who knows what in transportation. #3. When you shake the new valves will they rattle and does it seem like the pintle is spring loaded? it's not a heavy spring at all but it should have a light spring in there. #4. A video would help because we'd be able to tell you what we think of what we hear, but do remember a PCV valve is a metered vacuum leak so to speak, is it possible that the carburetor just needs to have it's idle mixture enrichened? If you attach a vacuum gauge to the manifold port will you get different readings with and without the PCV valve?
could he maybe be looking at advance weights sticking. my truck had sticky rusty advance weights and it wouldnt idle under 1k rpm or so without a lot of negotiating with my foot on the pedal in quick jabs. They wouldnt pull back to center
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I tried to back the screw out myself but then I ended up not idling when they wouldnt stick. So Im not certain if it could be a scenario where its always stuck out vs mine was just annoying gets stuck but could be brought back with attempts. Can OP pop his cap and rotor and just check? never hurts
 

SirRobyn0

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could he maybe be looking at advance weights sticking. my truck had sticky rusty advance weights and it wouldnt idle under 1k rpm or so without a lot of negotiating with my foot on the pedal in quick jabs. They wouldnt pull back to center
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I tried to back the screw out myself but then I ended up not idling when they wouldnt stick. So Im not certain if it could be a scenario where its always stuck out vs mine was just annoying gets stuck but could be brought back with attempts. Can OP pop his cap and rotor and just check? never hurts
True, but OP states truck runs correctly with PVC valve line plugged off
 

AuroraGirl

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True, but OP states truck runs correctly with PVC valve line plugged off
this would be interesting indeed. I have very little faith in the dollar store PCV, so thin and cheap and frankly inconsistent. Take 3 off the shelf of the same PN and they feel different. I feel he maybe has a truck with some blowby or maybe strng vacuum and its just holding open? any leak like a dipstick tube or valve cover gasket at that point because vacuum leak
 

Isaac nickerson

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Yup, that was it. I got that acdelco part yesterday and fixed the problem. No more cheap 3 dollar PCVs ever again. Thanks for the help guys.
 

AuroraGirl

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Yup, that was it. I got that acdelco part yesterday and fixed the problem. No more cheap 3 dollar PCVs ever again. Thanks for the help guys.
in my experience the AC delcos can be shoddy to but im glad it worked. definitely an order thing, not a store. the store never has the stuff in. For example, my SBC and my supercharged 3800 have the same autozone spec for PCV, as well as a 99 northstar v8, as well as a NA 3800, as well as you name it... and id like to see someone tell me to my face that a supercharged v6 has the same pcv valve as a smog NA small block chevy. albeit both are low compression pushrods in the end, its still the idea ya know?
 

Oaasport

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I always run a high quality PCV valve. I tossed it once while running a 1406 and it ran like piss. Replaced pcv valve and lightly adjusted idle screws and she started running great
 

75gmck25

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My PCV valve blew out of the valve cover grommet once when the engine backfired and it took me a while to find the disconnect and figure out why the engine was running so bad at idle. It definitely screws up the AFR when the PCV is not seated in the valve cover.
 

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