manifold vaccum for vaccum advance ?'s

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i dont understand how it could be mis firing? Wouldnt a miss fire be caused by old distributer cap and rotor and bad plugs and plug wires? everything on theis engine ignition wise is brand new including the distributer.
 
how do i check for it miss firing? look for sparks at night when its running?
 
I would start from scratch and use the "search" button at the top of this page. Type in "miss firing" for example and do some research. Not trying to be a smart *** but you will learn more that way than just keep asking questions. You will be miles ahead of the game another words.
 
pjc360 said:
I did have to take the intake manifold off to drill out 3 broken studs in the cylinder head on the drivers side.
And i put a new intake manifold gasket on it and then i put rtv silicone on all 4 corners of the intake manifold and put the intake manifold back on it. then my buddy grabbed his torque wrench and started torquing the intake bolts down and he broke another stud off into the cylinder head.

What were you torquing them to, they only need 35 ft lbs.

At this point i was so tired of drilling because i had been sitting there doing it for about 5 hours that i just threw some silicone down in the hole where the stud broke. And i have not got around to fixing it yet, Could this be causing the issue with the thudding out the exhaust? a vacuum leak?

Probably, with the car running spray some carb cleaner around the base of the intake, use the little plastic tube to keep the spray concentrated to a small area, if the idle changes (speeds up) then you have a leak.


 My uncle said when he had his vacuum gauge on it that the needle was moving around a little bit, and he said that it has a small vacuum leak somewhere. I need to know how to track a vacuum leak down, because i am sure that's what this is.
And yes i do have headers, hedman headers.

It's also possible that you have a bad gasket
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ok, i just sprayed carb cleaner around the whole base of the intake manifold with the engine cold and i used a brand new can of carb cleaner with the red tube and the idle never changed, i sprayed alot by the broken intake stud and nothing... Then i sprayed around the base of the carburetor still nothing. My hedders may have a couple leaks, because i can hear some ticking on the drivers side, is it possible for an exhaust leak to cause this to happen?
Also i triple checked my firing order and made sure the plug wires were nice and snug on the plugs as well as on the distributer cap. So whats my next move? I did notice some of the carburetor cleaner bubbling around the base of the intake, is this a sighn of a leak? or is it just getting warm on the intake? The intake manifold gasket i put on it was brand new.
I have noticed this issue before i even started messing with the timing or the carburetor, its just more noticeable with more timing, especially with the vaccum advance connected to manifold vaccum.
 
my vaccum gauage moves around a little bit, it does not stay steady while at an idle, wich i have been told indicates a vaccum leak, i'm wondering if it is too small of one to really change the idle when spraying carburetor cleaner on it. Is there such thing as an internal vaccum leak? like under the intake manifold? maybe that broken intake manifold stud is causing a little leak?
whatever it is, its driving me insane.
 
Another thing you might look at after it's nice and dark out. Take a spray bottle with water in it and set the nozzle to mist, spray some on your plug wires, just a little and start it up and see if you have spark jumping around anywhere.

You also should check and make sure your wires are all good.

I have had some popping in the exhaust in the past with an exhaust manifold leak. I'm not saying that's what your problem is, it could be a combination of things. Just keep eliminating the possibilities, you will find it sooner or later.
 
mullinax95 said:
I would start from scratch and use the "search" button at the top of this page. Type in "miss firing" for example and do some research. Not trying to be a smart *** but you will learn more that way than just keep asking questions. You will be miles ahead of the game another words.
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Badsport said:
Another thing you might look at after it's nice and dark out. Take a spray bottle with water in it and set the nozzle to mist, spray some on your plug wires, just a little and start it up and see if you have spark jumping around anywhere.

You also should check and make sure your wires are all good.

I have had some popping in the exhaust in the past with an exhaust manifold leak. I'm not saying that's what your problem is, it could be a combination of things. Just keep eliminating the possibilities, you will find it sooner or later.
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Oklacarcollecto said:
If not try using this.

http://www.forabodiesonly.com/mopar/search.php

I think you need to fix the manifold correctly and go from there. Gut feeling is this is where your problem starts.
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well i took the carburetor spacer off and that seemed to help the popping out the exhaust, but it did not eliminate it, so its not the carburetor spacer, its not the coil. couldnt find any vaccum leaks with carburetor cleaner and its obvious my valve guides are now totally ruined because i was barley on it and backed off the throttle and smoke came flying out everywhere lol this problem is making me so mad i'm just about ready to thro a for sale sighn in the dam thing and be done with it, let it be somone else problem.
How do valve guides become ruined? and would it be cheaper for me to get the valve guides replaced in the heads i have now? or would it be cheaper to just get new cylinder heads? I dont know how i meesed this valve guides up but they obviuosly are, it smokes when letting off the gas almost every dam time and it does when i'm not even pushing it that hard.
 
pjc360 said:
well i took the carburetor spacer off and that seemed to help the popping out the exhaust, but it did not eliminate it, so its not the carburetor spacer, its not the coil. couldnt find any vaccum leaks with carburetor cleaner and its obvious my valve guides are now totally ruined because i was barley on it and backed off the throttle and smoke came flying out everywhere lol this problem is making me so mad i'm just about ready to thro a for sale sighn in the dam thing and be done with it, let it be somone else problem.
How do valve guides become ruined? and would it be cheaper for me to get the valve guides replaced in the heads i have now? or would it be cheaper to just get new cylinder heads? I dont know how i meesed this valve guides up but they obviuosly are, it smokes when letting off the gas almost every dam time and it does when i'm not even pushing it that hard.
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you can fix the valve seals with the heads on the engine. a valve spring compressor and an air compressor. are you sure the rings arent shot? i havent read this entire thread so i dont know if this engine is new. have you done a compression check or a leakdown test?
 
16 sounds like a lot for initial timing, I would expect this to be in the 5 to 10 range.

What I have been told is that at high vacuum the engine is running lean and needs more spark advance. When you step on the gas and dump a bunch of fuel in the engine from the power valves and accelerator pump you no longer need that extra advance and just the mechanical advance is fine.

So try either reducing your initial timing, or leaning out your idle. with the advance connected to the manifold.
 
pjc360 said:
well i took the carburetor spacer off and that seemed to help the popping out the exhaust, but it did not eliminate it, so its not the carburetor spacer, its not the coil. couldnt find any vaccum leaks with carburetor cleaner and its obvious my valve guides are now totally ruined because i was barley on it and backed off the throttle and smoke came flying out everywhere lol this problem is making me so mad i'm just about ready to thro a for sale sighn in the dam thing and be done with it, let it be somone else problem.
How do valve guides become ruined? and would it be cheaper for me to get the valve guides replaced in the heads i have now? or would it be cheaper to just get new cylinder heads? I dont know how i meesed this valve guides up but they obviuosly are, it smokes when letting off the gas almost every dam time and it does when i'm not even pushing it that hard.
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What color is the smoke? If it is dark it will be fuel related. Light Bluish will be oil.
 
i dont know how to do a compression test or a leak down test. This engine is not brand new it was purchased in 2001. But it doesnt have many miles on it. About 25 to 30 thousand miles on it. It was purchased brand new by my dad, and he passed away 2 years ago so i got it and put it in a 91 short bed dodge 4wd truck.
I dont think the rings are shot because when i first start the truck up it doesnt smoke out the exhaust... yesterday was the first time i have ever seen it smoke out the exhaust. I was in second gear and reved it up to about 4500 to 4700 rpm and backed off the throttle and i seen the smoke come flying out the drivers side exhaust pipe, light blue smoke.
But i have fired it up and shut it off fired it up shut it off a few times watching the exhaust pipe and i never see any smoke come out of the exhaust when i fire it up. So i'm thinking the rings might be ok. I think its the valve guides that are letting all the oil blow by when i am on it good and let of the gas. I was just thinking if its time for a valve guide job then i might as well just get a new set of cylinder heads. I have been looking at the iron ram heads from hughes. Completley assembled and ready to go i think they are only 1000 bucks and they are better then the factory magnum heads. So i have been told anyways.
 
................Put in a new pcv valve............yes, u can have a vac leak under the intake....this is a magnum style right?.......there is a gasket under the intake between the intake and plate that bolts to it..on the fuel injected engines anyways......it is very common to blow out and suck oil......also u can have an internal leak between the heads and intake.......kim.........
 
it is a light color blue, its oil. And another thing i noticed when its parked and i rev it up to 4000 to 4500 rpm and back off the gas smoke doesnt come out the exhaust then, it only does it when i'm driving dwon the road and i get up to around 4000 rpm and back off the throttle then the light colored blue smoke comes out the exhaust pipe.
And i just started it and shut off 5 times watching the exhaust pipe and no smoke comes out the pipe starting it.
 
pjc360 said:
i dont know how to do a compression test or a leak down test. This engine is not brand new it was purchased in 2001. But it doesnt have many miles on it. About 25 to 30 thousand miles on it. It was purchased brand new by my dad, and he passed away 2 years ago so i got it and put it in a 91 short bed dodge 4wd truck.
I dont think the rings are shot because when i first start the truck up it doesnt smoke out the exhaust... yesterday was the first time i have ever seen it smoke out the exhaust. I was in second gear and reved it up to about 4500 to 4700 rpm and backed off the throttle and i seen the smoke come flying out the drivers side exhaust pipe, light blue smoke.
But i have fired it up and shut it off fired it up shut it off a few times watching the exhaust pipe and i never see any smoke come out of the exhaust when i fire it up. So i'm thinking the rings might be ok. I think its the valve guides that are letting all the oil blow by when i am on it good and let of the gas. I was just thinking if its time for a valve guide job then i might as well just get a new set of cylinder heads. I have been looking at the iron ram heads from hughes. Completley assembled and ready to go i think they are only 1000 bucks and they are better then the factory magnum heads. So i have been told anyways.
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Seriously, it is time for a pro before you destroy the engine all together.
 
pjc360 said:
it is a light color blue, its oil. And another thing i noticed when its parked and i rev it up to 4000 to 4500 rpm and back off the gas smoke doesnt come out the exhaust then, it only does it when i'm driving dwon the road and i get up to around 4000 rpm and back off the throttle then the light colored blue smoke comes out the exhaust pipe.

Sounds like valve seals to me, or an internal leak as mentioned sucking oil into the exhaust.


And i just started it and shut off 5 times watching the exhaust pipe and no smoke comes out the pipe starting it.
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Well its got a brand new pcv valve already... i just put a brand new pcv valve in it a couple of weeks ago... And this is a magnum 360, but it is not fuel injected It is carburetated. When i took the intake manifold off the engine and out it back on there wasnt a gasket under the intake manifold? there was two gaskets that covered the sides and gasket part that covered the front and back and then i silconed all 4 corners.
Maybe this broken intake manifold stud is causing all the problems, thats the only thing i can think off, its mot likely a vaccum leak between the head and the intake but the leak is not visible to me because its under the intake where the broken intake stud is.
But still wanna find out if my valve guides are trashed,
Is there a way to find out if the valve guides are ruined? whats the easiest way to find out?
 
time for a pro before i hurt the engine? I'm trying to learn here, how would i ever learn how to do this if i jut dumped it off on somone else to fix lol
 
pjc360 said:
Well its got a brand new pcv valve already... i just put a brand new pcv valve in it a couple of weeks ago... And this is a magnum 360, but it is not fuel injected It is carburetated. When i took the intake manifold off the engine and out it back on there wasnt a gasket under the intake manifold? there was two gaskets that covered the sides and gasket part that covered the front and back and then i silconed all 4 corners.
Maybe this broken intake manifold stud is causing all the problems, thats the only thing i can think off, its mot likely a vaccum leak between the head and the intake but the leak is not visible to me because its under the intake where the broken intake stud is.
But still wanna find out if my valve guides are trashed,
Is there a way to find out if the valve guides are ruined? whats the easiest way to find out?
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Do a compression test and a leak down test.
 
so how do i perform a leak down test? i have alot of tools. i probably have every tool i would need to do this. I dont know a whole lot because if i ever had any issue like this my old man would take over and fix whatever it is. But i wanna learn how to do this kinda stuff myself. So if somone would like to walk thru on how to do a compression test and a leak down test i'd really appriciate it.
 
pjc360 said:
so how do i perform a leak down test? i have alot of tools. i probably have every tool i would need to do this. I dont know a whole lot because if i ever had any issue like this my old man would take over and fix whatever it is. But i wanna learn how to do this kinda stuff myself. So if somone would like to walk thru on how to do a compression test and a leak down test i'd really appriciate it.
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Google it and you should find a You Tube video that will show you step by step.
 
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