I have been researching the ignition system for a '91 ranger 4.0 because I have a no-start problem. I don't know if cali. has a cam position sensor but everything I've read says the 4.0 doesn't. There is a crank position sensor [ckp] that sends info to a ignition control module [icm]. The icm sends info to the computer [pcm or eec] and the eec figures out how much timing the engine needs and sends that info back to the icm. The icm then tells the coil-pack when to fire the proper coil.
The eec is behind the passenger side kick panel [I think as I have moved pretty much everything in my truck]
The icm is on the radiator core support passenger side beside/under the headlight. It has a green sticker saying EDIS6. EDIS6= electronic distributor ignition system 6-cylinder
The ckp is beside the crank snout passenger side.
First thing I would do after a cel test, is check all grounds are clean and use di-electric grease to promote a long lasting good ground. I have found several ground wire connections, on both inner fenders,core support, firewall, starter mounting bolt,engine manifold, battery......
On my truck I found one bolt missing for the ckp but it would still run at the time

I found two spout connectors, neither were connected. The icm doesn't need eec input to run the engine, it will just default to 10 degree before tdc [top dead center].
There is a free diagnostic at the autozone website, it looks to be word for word copy of my chiltons diagnostic. By the way, the quick test they refer too is checking for codes: a cel test [cel=check engine light]. I'm at the limit of my knowledge now,
Good luck,
Richard