PID (parameter ID)

An identifier for a single live data channel (a sensor reading or computed value) that VCM Scanner can request and log from the ECU.

A PID, or parameter ID, is the address/identifier for one piece of live data the ECU can report, such as engine RPM, manifold pressure, coolant temp, commanded AFR, spark advance, or knock retard. VCM Scanner reads PIDs to build its gauges, charts, and histograms. Some PIDs are standard OBD-II; HP Tuners also exposes many enhanced, vehicle-specific PIDs plus Math Parameters you define from other PIDs. PIDs matter for safe tuning because they're how you see what the engine actually delivered: logging both commanded AFR and a wideband AFR PID lets you confirm the two agree before adding load or boost, and logging knock PIDs warns you before damage. Be aware that adding many PIDs lowers your logging sample rate, so log the channels relevant to the change you're making. In Scanner you add, remove, and arrange PIDs through the channel/parameter selection menu when configuring a layout.