AutoPSI Sensors
PSIplug: Modified Spark Plug with Removable Pressure Sensor
PSIglow: Glow Plug with Integrated Pressure Sensor
PSIglow-A: Glow Plug Adapter with Built-in Pressure Sensor

AutoPSI (-S, -TC,-HT)


All AutoPSI sensors have the signal conditioner incorporated into a small metal shell permanently connected to the end of 2m (6.5') fiber-optic cable. The AutoPSI-S offers the most economical solution for dynamic pressure measurements. The temperature-compensated AutoPSI-TC sensor matches the perfomance of water-cooled transducers. The AutoPSI-HT comes with the signal conditioner rated for 125°C and a three year lifetime guarantee.

AutoPSI sensors are available in a variety of packages and pressure ranges. Custom design packages are available on request - see the Accessories page.



The PSIplug integrates a customer selected, modified production spark plug with a removable, non-invasive pressure sensor. The sensor is located in an adapter which is mounted as close as possible to the spark plug cavity minimizing errors caused by long pressure passages found in custom built sensor/spark plug systems. By using a production spark plug, flame formation and propagation characteristics are not affected. The pressure sensor is interchangeable with other Optrand modified spark plugs making the PSIplug a cost effective solution for applications demanding various plugs.

View PSIplug flier (700k PDF)


The PSIglow™ integrates Optrand's miniature 1.7mm diameter sensor with a fully functional glow plug allowing for combustion pressure monitoring of diesel engines without head modification or loss of glow plug functionality. The PSIglow is ideal for cold start studies, heat release analysis, and advanced engine control and monitoring techniques. The sensor is mounted in the glow plug sealing surface with its sensing diaphragm directly exposed to the combustion chamber without any connecting passages eliminating errors introduced by long and thin gas passages. The miniature sensor diaphragm features minimal thermal shock and related high accuracy at low pressures without any heat shields or flame quenchers, permitting lifetime use in production engines.

View PSIglow flier (70k PDF)


The PSIglow-A pressure sensor adapter utilizes a customer supplied glow plug which is modified to accept an AutoPSI pressure sensor. The resulting package has identical volume to the original plug and allows for direct pressure readings without any head modifications. The PSIglow is available in the standard (-S), temperature compensated (-TC), and high-temperature electronics (-HT) variations of the AutoPSI sensor system and provides a low-cost, non-invasive solution for combustion pressure monitoring and testing of diesel engines.

View PSIglow-A flier (700k PDF)