Chrysler Repair: 95 t&c 3.3L: no spark to out of #3-6 at coil, primary coils, cam sensor

Question
QUESTION: i have changed coil, plugs and wires. still no spark. i ohmed the wire from coil (red) wire to pin 18 on computer connector it is good ohmed wire to ground it is not shorted. other 4 plugs fire and van runs. fliped key to get codes shows cylinder misfire( i already new that). help please

ANSWER: Hi Mike,
If you have established to your satisfaction the reliability of the red/yellow wire and have replaced the coil, then I would suggest the two remaining possibilites are that the signal from the cam sensor is weak for that rotational position of the engine due to either a failing sensor or more likely the sensor is not positioned properly to read those slots on the cam surface OR that the pcm is faulty and must be replaced. I will let you explore the relevant costs of pursing those two options. You might get a new paper spacer for the tip of the cam sensor from a dealer parts counter and try reinstalling it, as that would involve minimal cost.
Roland

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QUESTION: hi roland, i changed the cam sensor today(that was fun) still the same problem is there any way to check the sbec before i change it. i know the wires coming from it to the coil, should i get voltage from the control or ground on the 3 wires to coil pack. can i check voltage from B or common terminal on coil to each of the wires to coil. what should the voltage be. is there anything else i should check. thank you

Answer
Hi Mike,
The dark green/orange wire should have 12V on it whenever you are cranking it over or the engine is running (that is provided by the ASD relay). That voltage is applied in common to one end of all three of the primary coils, and the other ends of those coils are the three other pins of the coil pack. For a coil to spark, the other end of each primary winding has to pulsed momentarily to ground by the pcm wire coming from its respective pin at the pcm. Depending upon your voltmeter you may be able to see that pulsing to be present because it will give an rms voltage reading of something less than 12v, but the pulses may be going by so fast that the meter won't notice it, but give it a chance by comparing the voltage readings for those three signal wires while the engine is idling. If you see a difference (such as a higher reading on the 3/6 pin) then that would show either that the pcm for that wire is bad, or the primary winding for the 3/6 coil is bad (although you did replace the coil so that is unlikely). As far as the coil verification is concerned, the resistance between the common 12v pin of the coil and each of the other three pins should be 0.45 to 0.65 ohms, and the resistance between the high tension outputs sockets of the three pairs should be 7,000 to 15,800 ohm, should you want to verify the coil pack is up to spec.
Roland