no power to ignition coil

[Farrar]

Sparky has developed a no-start problem. The starter motor turns, but there is no spark.

I have checked the fuses, ballast resistor, relays, etc. and all are functioning, but the ignition coil is not receiving more than a few volts with the key on.

What are the points of failure I should check next?

Thanks in advance.

[David T]

Sparky has developed a no-start problem. The starter motor turns, but there is no spark.

I have checked the fuses, ballast resistor, relays, etc. and all are functioning, but the ignition coil is not receiving more than a few volts with the key on.

What are the points of failure I should check next?

Thanks in advance.

The most common problems in the ignition system are:
bad connections (rusty) on the ballast resistor
bad impulse coil
bad ignition coil (especially if it is a high performance coil, non-original coil)
Low battery

There are some diagnostic checks you can do on M:01:03-:4 in the Workshop Manual. If you can get your hands on the DMC Technical Service Manual, there is a great diagnostic tree checklist for an ignition no start table C1

[JohnZ]

I have had the same problem last days. Be sure of the battery being fully charged! (Sounds silly but that's that... )

[Bitsyncmaster]

There is a pretty large voltage drop just with the OEM harness. So if your running a lower resistance coil at higher current then that may be causing the drop.

I think its normal to see about 4 volts on the coil without the engine running with the stock setup. Resistors drop half the voltage, ignition ECU only drives the ground to about 1 volts and the wiring drops the rest.

[Farrar]

With key in "run" position, battery 12v, coil 6v. Still no spark, no start.

[Michael]

Make sure the little connection from the ecu through the firewall to the coil harness has not come lose. Those never fit that well to begin with. You can find it on the left side (driver) firewall below the resistor but near the frame. Remember it may still look connected.

[Rich]

Factory Troubleshooting Chart - Engine Will Not Start

First two images in this Resource post are both pages of Chart C1, Ignition. After they first appear in medium size sure to enlarge each on with an extra click.

LINK: http://dmctalk.org/showthread.php?3142-Factory-Troubleshooting-Charts-Engine-Will-Not-Start

Looks like with >11V at Batt. and 6V at coil (chart is asking for 6-8V in Test #2) you can go on to Test #3 on pg 1.

There are 5 tests listed in C1, pgs 1-2.

[Farrar]

Factory Troubleshooting Chart - Engine Will Not Start

Thanks, I must have forgotten about that tech manual I bought back in 2007...

[Farrar]

Make sure the little connection from the ecu through the firewall to the coil harness has not come lose. Those never fit that well to begin with. You can find it on the left side (driver) firewall below the resistor but near the frame. Remember it may still look connected.

Thanks, I'll go searching for that tomorrow if I get the chance...