Abstract: A capacitive sensor for a coil-on plug ignition testing apparatus includes a first portion of the capacitive sensor and a second portion of the capacitive sensor, at least one of which has a substantially planar base, and each of which has one or more engagement members projecting downwardly therefrom. One of or both of the first portion and the second portion may be a capacitive element forming a part of the capacitive sensor. The second portion is connected, and is configured to slide relative, to the first portion. A biasing element is disposed between the first and second portions to bias the first portion toward the second portion and to maintain the first portion and second portion in a compressed state. The first portion may be translated relative to the second portion against a bias of the biasing element, to an extended state for securing to a coil-on plug housing.

Abstract: Engine cylinder contribution analysis is provided. An engine cylinder contribution tester includes a displacement measurement device and a signal analyzer. The displacement measurement device detects engine block movements or displacement relative to a fixed position caused by a poorly contributing cylinder. The displacement measurement device provides a displacement signal to the signal analyzer. The signal analyzer includes a cylinder contribution module for evaluating the displacement signal. If a particular cylinder is contributing less than the average of the other cylinders, the displacement signal indicates engine block movement associated with a lack of contribution from that cylinder.

Abstract: A capacitive sensor for an ignition testing apparatus includes a substrate bearing a sensor metallization and a ground metallization, an output lead, a mounting device integrated with the substrate and configured to permit the substrate to be releasably mounted to an ignition coil housing, and a sensor displacement assembly integrated with the substrate and/or the mounting device. The sensor displacement assembly includes at least one member configured to move at least a portion of the sensor metallization in a first direction toward an ignition coil housing and/or a second direction away from an ignition coil housing and/or a third direction lateral to the ignition coil housing while the substrate is mounted on an ignition coil housing using the mounting device.

Abstract: A variable compensation circuit for capacitive adapters is provided and includes an input connector for receiving a signal output from a capacitive adapter positioned within an electric near field emitted from a component of an engine ignition system, an output connector for outputting a signal output from the variable compensation circuit, a capacitive divider circuit portion disposed in series between the input and output connectors, the capacitive divider circuit portion comprising at least one of a variable capacitor and a plurality of fixed capacitors. The variable compensation circuit also includes a switching element configured to enable at least one of a selection and de-selection of the plurality of fixed capacitors and adjustment of a variable capacitor to provide one of a plurality of selected capacitance reactance ratios.