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#2
The EGR when open pulls its intake air from #3 cylinder intake runner effectively killing that cylinder. Make sure theres no vacuum to the EGR at idle. If you have a 12 volt test light you can isolate the cylinder thats missing by probing the plugwire boot. If it is not missing but rather loping then the A/C idle up might need adjustment. There is an idle switch on the front of the carb at the bottom also. It's a simple on/off switch. There is a slow fuel cut solonoid on the carb firewall side that controls fuel flow at idle. It has 2 wires and can be easily removed/tested. Use carb spray to clean that circuit out while you have it off.The fuel misture screw has a tamper pin in it.Fuel mixture is adjusted with a dwell meter from a 1 pin connector at the firewall on the passenger side.The dwell should fluctuate from 40-70 degrees dwell warmed up at idle.