occasionally get Ignitors returned to us that have failed.
In the great majority of cases it is the result of misuse, miswiring or
problems with the vehicle electrical system (see Low
Voltage) and not the fault of the Ignitor.
In order of occurrence, here's what we find in cases of failure:
1. Key is left on
without the engine running with a standard Ignitor.
If the engine happened to stop in a position analogous to points closed,
the Ignitor will continue to try to charge the coil without the coil discharging
resulting in excessive heat which can fry the Ignitor.
If the engine happened to stop in a position analogous to points open,
the Ignitor/coil circuit would be open, no current would flow, and there would
be no damage to the electronics.
2. A low resistance
aftermarket coil is used that does not have the resistance required by the
Ignitor as stated in the instructions (1.5 ohms for an 8 cyl, 3.0 ohms for 4 and
6 cyl, assuming a 12 V system). The
coil resistance is what regulates the current in the Ignitor/coil circuit. Too low a resistance results in too high a current in the
circuit that can overheat the electronics.
The failure may not happen immediately but the excess heat will shorten
the life of the electronics. How
long the electronics will last will depend on how much heat is generated.
It could be a matter of a couple of hours to a few hundred hours
depending on temperature.
3. Polarity reversed
when wiring. This will fry the
electronics quickly on a standard Ignitor.
automatic shut-off feature in the Ignitor II prevents damage in all three cases
It is not
uncommon for an older car to have its electrical systems modified
at some time in its history, not always for the better. It is
important to make sure the circuit to the Ignitor is as it should be.
is possible for an Ignitor to fail on its own, but this is the case in only a
very small percent of the Ignitors that are returned.
Ignitors that are
returned test out to be working perfectly indicating a problem with the vehicle
in which they were installed. Of the ones
that have failed, we can usually trace the reason to one of the causes listed
Suppression-type spark plug wires required. Do not use solid core wires.