Rough and shaking 350 after changing spark plugs

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newguy11

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Iv always taken the vacuum hose down to the auto parts store, here in the states hose and wire is often sold by the foot and is in spools at the store
 

Ricko1966

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Sir I reread your post and I did get yours and gtx63s post mixed together. I have reread your original post. Now if you just replaced ignition components etc. Go back and triple check everything you've just done prior to the problem,like if I got new shoes and today my feet hurt,my first suspicion is going to be somethings wrongvwith these shoes. I would suggest not throwing parts at it until you've actually diagnosed it,you may accidentally create another problem and chasing 2 problems and tried to figure out which is which makes things a lot harder. That being said the biggest possible vacuum leak that I can think of that would be temperature dependant would be the EGR valve pull the hose off at the egr end and plug the hose,see if your problem goes away. I'd still spray underhood,in the dark with salt water,amazing what can show up. If after egr is out of the equation plug all the vacuum hoses,don't mix them up,plug them all. Problem gone? Start plugging them back in one at a time,if the problem comes back you found the answer. Put a vacuum gauge on it,tell us your readings cold and hot.
 

Rusty Nail

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Hold on. He said TWICE that it ran fine for the first 30 miles then started running bad, right?

OK. After the thermostat opens. I think you guys are barking up the wrong tree.
AND THEN he showed a picture of an unplugged thermostatic switch. We're getting warmer.

My first thought was quickly "cracked spark plug insulator during install.
AND THEN
You dudes started talking about vacuum lines...look at the thermostatic vacuum switch on the thermostat housing. Pretty sure it has two vacuum hoses on it. One runs to the air cleaner, where does the other one go? Not on the diagram.... in your truck where does it go? If it goes to some sensor - replace it.

those are the two places EYE would look first. Replace that switch and eliminate it as an option.

We'll send a bill or you can buy a bumper sticker. :waytogo:
 
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Dave15

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well i threw an eye on the thermal vacuum switch and look at this little moth******** hitten under the fresh air snorkel
those vacuum hoses are crunchy like cereals
 

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Dave15

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i know, but i can imagine how this hose broke. i changed the fuel filter too, came to my mind when i saw this crack.
it's realy close and could be the mystery but i will change the ignition parts anyway and tomorrow i will by a couple of feet vacuum hoses and change them too.
the car is 37 years and if those are still the original ones a change can't be so wrong even if its not the problem but it may safe me from a headache in future.
 

Trucksareforwork

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well i threw an eye on the thermal vacuum switch and look at this little moth******** hitten under the fresh air snorkel
those vacuum hoses are crunchy like cereals
That’s the likely culprit for the behavior you are describing. I would do a quick check on all the vacuum tubing. If the rubber stuff is that crunchy, the plastic stuff is likely brittle too.
 

Dryriver1

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well i threw an eye on the thermal vacuum switch and look at this little moth******** hitten under the fresh air snorkel
those vacuum hoses are crunchy like cereals

Quick cut off 1/2 inch or so then re-install it and check it. If it fixes the problem then you got that one problem fixed and buy all new vac lines.

Then recheck all the wires, cracked plugs under the rubber insulators, cap & rotor, and would check to make sure that the distributor did not move on you also.

Just my way of thinking...

Hold on. He said TWICE that it ran fine for the first 30 miles then started running bad, right?

OK. After the thermostat opens. I think you guys are barking up the wrong tree.
AND THEN he showed a picture of an unplugged thermostatic switch. We're getting warmer.

My first thought was quickly "cracked spark plug insulator during install.
AND THEN
You dudes started talking about vacuum lines...look at the thermostatic vacuum switch on the thermostat housing. Pretty sure it has two vacuum hoses on it. One runs to the air cleaner, where does the other one go? Not on the diagram.... in your truck where does it go? If it goes to some sensor - replace it.

those are the two places EYE would look first. Replace that switch and eliminate it as an option.

We'll send a bill or you can buy a bumper sticker. :waytogo:

Then what Rusty Nail said here in Bold... :favorites13:
We'll send a bill or you can buy a bumper sticker. :waytogo:

Dave please keep us posted.
 

Dryriver1

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well i threw an eye on the thermal vacuum switch and look at this little moth******** hitten under the fresh air snorkel
those vacuum hoses are crunchy like cereals

Hello Dave15.

Inquiring to see if the problem got fixed?
What was it just the vac lines, was there also a problem with the plug wires?

Keep us posted.
 

Dave15

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Hello Dave15.

Inquiring to see if the problem got fixed?
What was it just the vac lines, was there also a problem with the plug wires?

Keep us posted.
will give you the results hopefully tomorrow, parts should arrive in the morning
 

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