420 SEL One cylinder skips at warm idle.
The number 5 cylinder begins to skip about 30 seconds after the car is started. Idle is 900 rpm. I checked spark, changed the distributor cap and rotor, switched plug wires and switched plugs with no improvement
The cylinder seems to kick in at about 1500-2000 rpms both under load and without load. but as the engine gets warmer (normal temp) acceleration is sluggish and it sounds like the engine is starving. I removed the fuel lines from the #5 cylinder and the #4 cylinder and the fuel flow seems to be about the same for both at idle. The fuel line to #5 does not seem to be restricted.
I am certain that spark is not the problem.