[goatnut]

Sounds like a bad spark plug or wire. This is generally called a low speed miss. The engine is operating at low rpm with trans in high gear and torque conv locked. The ignition system has to work harder when at low rpms and if you have a weak spark plug or wire it will show up under this condition. There are more things that can cause a low speed miss but the spark plugs and more times than not its a defective spark plug wire. Also check the coil towers where the spark plug wires attach to the coil they like to get rusty there. Just clean the rust from the terminals and coat with dielectric grease and replace the wires. Hope this helps you out.