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#4 cylinder has a sporadic spark. It is bright then week. Misses often to. Other side of that coil fires fine. I rplaced plugs, wires and coil pack for intake/compression side. Did not change the spark. This model does not have an ICM. The ICM is integrated into the PCM. Could the PCM be the problem? What about the crank sensor?
pointer finger is indicating #4. Pinky finger indicates terminal that misses every now and then.
Ford uses Waste spark so there are only 2 coils in each coil pack, not 4
So in your 2.3l cylinder 1 and 4 use the same coil in each coil pack, wired in series(2 and 3 share the other coil in the pack)
So you can reverse 1 and 4 wires at the coil pack to see if problem changes to #1 on that coil pack
Also because there is no external ICM(spark module), engine can be run with either coil pack disconnected, the 2.3l ran fine from 1974 to 1988 on just 4 sparks
So unplug the 3 wire connector, on either coil pack, and start engine, see if there is a steady misfire, bad wire or plug
It will idle lower and have a little less power on a drive but should run smooth on just one coil pack
Then reverse it, plug in the coil pack and unplug the other
Steady misfire on either coil pack means wire or spark plug, and if you drive it you should get a misfire code IDing which cylinder is misfiring, P030X
Yes, it is possible for computer to fail and not ground a coil in the pack, but long shot at best