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Discussion Starter #1
I have a 1978 pontiac trans am. Its been sitting for years and tryed starting it the other day to find it has no spark. So I bought a new distributer cap and roter, new ignition module, new spark plugs and wires, and a new coil. Everything in the distibuter is new and it still has no spark. There is power going to the coil from the battery wire that plugs in to it. Im just totally baffled and I could really use some help on this.
 

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need to pull cap off and then spin motor over look to see if the rotor turns if it dont you could have a broke timing chain or broke cam or gear if it does spin hook a hot wire from the batt
+ side to the dist. cap wear it says batt then spin it over should have spark if not you still have a bad dist or coil let me know if it still does not work
steve
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Discussion Starter #5
I tried the wire running straight from the battery and I checked to see if the rotor was rotating, everything is good. Im looking in to what you said about the pick up coil, that just might be it, thats the only thing i didn't replace on the distributer. I has to be it, theres nothing else it could be. I'll replace it and see what happens.. thanx
 

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dont forget your ground without a ground your coil cant build up power, by making breaking your ground is how it sparks make a ground is builds power break the ground it sparks
 

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You are dealing with too many things all at once. Make it simple to start with.

Check to be sure that when you turn the ignition switch on that you have power to the coil. If not, you will get no spark.....solve that problem.

Disconnect the coil from the distributor and put a spark plug into the end of the coil wire and ground it. Then intermittantly break the power to the coil. Each time you do that, the plug should fire.

If you get the plug to fire this means you have coil spark. Then move to the distributor. If you have spark, the distributor's job is to move the spark from terminal to terminal as the rotor spins. The breaker or optical trigger's job is to interrupt the power to the coil so that the coil is refreshed at the same time that the rotor comes around to each post. If you spin the rotor, it should cause the coil to fire the same way that interrupting the power to the coil caused it to fire. If it doesn't then the distributor is not interrupting the power to the coil. Find out why. If you get this to work, then move to the cap and rotor until you get it to work....check the spring load on the carbon in the center of the cap. It needs to make constant contact with the top of the rotor. This is how the coil transmits the charge to the rotor.

Be logical, move from simple to complex as you solve each simple problem, then combine them and you will have a working system.
 
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