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Discussion Starter #1
So I have a neighbor who just bought a little 66 Mustang coupe. It has a 302 2bbl in it and was running pretty well when he bought it. We went to go adjust the carb and realized it needed a rebuild. So we rebuilt the carb and in the process we decided to do the normal tune up on it. So we got a new coil, new condenser, new points, new rotor, new cap, new spark plugs gaped at 35, and new spark plug wires. So we put it all on today and the engine does not like us.

No matter where we set the timing 8 all the way up to 20 the engine shakes and shakes. It never did this before. When we go listen to the exhaust you can hear it sputtering. No mater what I do it shakes. If I have the fuel adjusted really lean (just a standard 2100 carb) it does it, if I run it rich is does it. If I move the timing around it does it. Any idea's on what it could be, because I'm all out of ideas.
 

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Bad plug wire maybe? I have seen the house brand stuff be bad out of the box. Break out an ohm meter and check them one by one. They should all be relatively close, in the 1000 to 2500 range. Or maybe the points gap is out of whack. I would check the firing order for 351 as stated before as well.
 

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Check the little ground wire inside the distributor cap. When you replaced the condenser and points, did you leave out the ground wire that connects the advance plate to the housing? The car will run rough if this wire has more than 1 ohm of resistance or is not properly grounded.
 

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Discussion Starter #12
Thanks for some idea's.

The ground wire I did not change, but did make sure it was tight. I'll check into that.

I'll also check into a possible bad plug wire. I'll let you know what I find as I work on it tomorrow.
 

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Why did you change the coil? Try changing it back to the original one.
 

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Assuming you've tried all of the above, check the plug wire to distributer cap insertions, I've had the metal connector back up into the rubber boot & not make good contact in the cap. Last resort for me is to start reinstalling each old part, while testing motor each time. it's tedious, but might be worth a try. Start with the condenser, it's easy & a high probability. Good luck, and let us know what ya find!
 

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Discussion Starter #16
I messed with it some more today with no luck. It still shakes and is not happy. I tried the 351 firing order with no luck as well.
 

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Cougar Boy, Time to break out the starter fluid and check for a serious vacuum leak. My guess would be that carb to manifold gasket or if you have a spacer the gasket there is going to be your culprit.
 

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Just guessing, but is it possible that the #1 spark plug wire isn't in the #1 hole in the distributor cap, and all the wires, while in the proper order, are rotated 1 hole off?
On a related note, I've seen shadetree mechanics stab the distributor wrong, and to make everything line up and work, intentionally install the wires a hole off. If someone previously did this, and you installed the wires as they should be, it could cause these symptoms.
Also, any idea what the 302 is out if? What year it is? Any custom mods?
 

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x 3 on the vac leak most likely - or you got something outta whack in the carb now. See if the spray test finds anything, if not, Pull that carb back off and giver another going through and double check that you didn't miss something - particularly the idle circuit.
 
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