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I could use a little help. I am working on replacing the dash circuit board on my 69 with factory tach. The car was running well before I started taking the dash apart. I unplugged the instrument cluster and removed it. Now the car will not start. It turns and starts, but dies as soon as you release the key to run. Does this have anything to do with this removal of the instrument cluster/tac/ resistor? or are they unrelated. Could it be a faulty ignition switch. The car is getting fuel and I had someone turn the key and grounded the distributor coil lead and it is getting plenty of spark while attempting to start?
 

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Your coil has 2 circuits of power. The primary circuit is from the switch in the run position. The second circuit is from the starter solenoid when the switch is in the start position. The primary circuit usually feeds a lower voltage either by a ballast resistor or a resistor wire (pink wire). Based on what I've read, this lower voltage keeps the coil temperature down to increase the life of the coil. The second circuit (from the starter solenoid) feeds a full 12 volts to the coil to aide in starting the engine. History lesson over. :)

Based on the above, it sounds like you somehow disconnected the primary circuit while you were working in the dash. I'd look for a disconnected wire.
 

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Disconnect the tach and you have broken the primary circuit. Power goes from the ignition switch through the tach through the resistor wire to the coil + terminal.

You can install a jumper in the tach connector to 'bypass' the tach and complete the circuit - that's what you have to do when the tach dies.

The car is 'firing' during start because the coil is receiving B+ voltage from the I post of the solenoid during start.
 
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