Welcome Visitor! Please take a few seconds and On spark systems everything starts at the "points", when switched to electronic these can be the hall effect sensors in the distributor or the variable reluctance(VR) CKP(crank position) sensors on the crank shaft.
The VR sensors generate their own "power", it can be read using volt meter set for AC power, should show about 1volt when crank is spinning at starter motor speed, and it will vary a bit, above .3v is OK.
Voltage is generated by crank speed so lower spin speed = lower voltage.
The CKP also needs a close proximity to the "tone ring", each tooth on the tone ring causes the CKP to generate a voltage pulse, the closer the tooth the higher the voltage.
This system operates using magnetic fields, so the closer the better.
A CKP tone ring will have 36 teeth minus 1 tooth, 1 tooth every 10 degrees(360 degrees full circle) the gap where 1 tooth is missing tells the EDIS when #1 piston is at TDC for correct timing.
If a second tooth gets damaged, then EDIS module won't know when #1 TDC is and won't start the spark.
It needs 35 pulses then a gap, or it won't work.
So give the tone ring the once over.
If CKP VR sensor is generating AC voltage then next stop is the EDIS module.
It needs power and a good Ground, the coils are grounded at the EDIS to power up then unGrounded to send out a spark, so if EDIS doesn't have a good ground then coil never powers up, so can't spark.
The coil itself is a pretty simple device.
The primary coil(loop of wire) has say 100 turns(coils), the Secondary has usually 80 times that.
Primary coil has 12v and a ground, powered up, when the power is cut, the ground removed in this case, then the collapsing electro-magnetic field transfers power to the Secondary wiring where the 12volts is multiplied by the extra coils in that wire, and you end up with 30,000+ volts but low amps, to jump the gap on a spark plug.
There are 3 sets of these in a V6 Coil Pack, 3 Primary coils each with it's own Secondary coil
On the old systems the points would open, cutting the ground to the coil, by being pushed open by lobes on the distributor shaft, then close again to repower the coil between lobes.
System still works the same just better now with less moving parts to wear out.
The VR sensors generate their own "power", it can be read using volt meter set for AC power, should show about 1volt when crank is spinning at starter motor speed, and it will vary a bit, above .3v is OK.
Voltage is generated by crank speed so lower spin speed = lower voltage.
The CKP also needs a close proximity to the "tone ring", each tooth on the tone ring causes the CKP to generate a voltage pulse, the closer the tooth the higher the voltage.
This system operates using magnetic fields, so the closer the better.
A CKP tone ring will have 36 teeth minus 1 tooth, 1 tooth every 10 degrees(360 degrees full circle) the gap where 1 tooth is missing tells the EDIS when #1 piston is at TDC for correct timing.
If a second tooth gets damaged, then EDIS module won't know when #1 TDC is and won't start the spark.
It needs 35 pulses then a gap, or it won't work.
So give the tone ring the once over.
If CKP VR sensor is generating AC voltage then next stop is the EDIS module.
It needs power and a good Ground, the coils are grounded at the EDIS to power up then unGrounded to send out a spark, so if EDIS doesn't have a good ground then coil never powers up, so can't spark.
The coil itself is a pretty simple device.
The primary coil(loop of wire) has say 100 turns(coils), the Secondary has usually 80 times that.
Primary coil has 12v and a ground, powered up, when the power is cut, the ground removed in this case, then the collapsing electro-magnetic field transfers power to the Secondary wiring where the 12volts is multiplied by the extra coils in that wire, and you end up with 30,000+ volts but low amps, to jump the gap on a spark plug.
There are 3 sets of these in a V6 Coil Pack, 3 Primary coils each with it's own Secondary coil
On the old systems the points would open, cutting the ground to the coil, by being pushed open by lobes on the distributor shaft, then close again to repower the coil between lobes.
System still works the same just better now with less moving parts to wear out.
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