Universal capacitive adapter for engine diagnostics

A method for diagnostic testing of an ignition coil, comprising the steps of:

• mounting in an initial position on an ignition coil housing a capacitive adapter comprising a substrate bearing a sensor metallization and a ground metallization, a mounting device integrated with the substrate and configured to permit the substrate to be releasably mounted to an ignition coil housing, an output lead, and a sensor displacement assembly integrated with at least one of the substrate and the mounting device comprising at least one member configured to move at least a portion of the sensor metallization in at least one of a first direction toward an ignition coil housing, a second direction away from an ignition coil housing, and a third direction lateral to an ignition coil housing, while the substrate is mounted on an ignition coil housing using the mounting device;
• connecting the output lead of the capacitive adapter to an engine analyzer;
• measuring a firing line signal output by the ignition coil using the capacitive adapter;
• and
• adjusting a position of the capacitive adapter sensor metallization relative to the ignition coil housing in at least one of the first direction, second direction, and third direction to obtain a first measured peak firing line signal within a prescribed range.