QuestionI am only getting fire on coil pack #1/4.On cylinders 2/5 and 3/6,have no fire.Checked wiring from PCM to coil,have 12 volts to power,on coil wiring I have .2 to.3 ohms in wires from coil to PCM,so wiring appears good,tried new PCM and new coil pack still only fire to 1/4,it will spark 1 time cylinders 4 and 6 when turning the engine over,but stops after that.When van came in wire harness to cam sensor had gotten into serpentine belt and chafed the harness,I replaced cam sensor,now good wave forms,also checked crank sensor.I have tried 3 reman PCM's from Chry all do the same.I unhooked TPS,MAP,AIS,both 02 sensors,can't find solution,have you seen anything like this before,I have fuel pressure,engine cranks fine,no codes,thought maybe jumped time,but I would think as long as it would see cam and crank inputs it (PCM) should ground out the coil to produce spark. Thanks Gene
AnswerHi Gene,
Have you watched the pulsing of the cam and crank sensor signal wires as you rotate the engine by hand? They whould oscillate between 5 and 0.3V many times per revolution. I wonder if the sensors might be slightly too far from the surface that they intersact with? Are the paper spacers worn away? It may be that there is a bit too much 'play' in the cam bearing such that the surface is not closs enough to the tip of cam sensor at all positions. Check to see if you get pulsed grounding of the three coil wires as you rotate it by hand, also.
Please 'rate' my answer (see below).
Thanks,
Roland
PS Sorry for the delay but I just found your question in the 'pool' to which it had been referred by Kevin.
