P0394: A bank 2 exhaust cam pulse can arrive in the wrong place

P0394 is Ford's intermittent bank 2 exhaust cam-position circuit result. The monitor description identifies a cam signal appearing at an unexpected location, so pulse presence alone is not enough to establish correct operation.

Evaluate the event sequence

Ford compares engine-position events with cam events using ratios that vary with cylinder count. A captured signal must be interpreted against the correct engine's reference pattern. Otherwise, a normal configuration could be mistaken for an extra or missing event.

The source lists continuous monitoring, an engine-speed entry condition of 200 rpm and a duration below five seconds. A scan-tool cam angle observed after the disturbance may be plausible even though the event relationship was temporarily invalid.

Keep bank and failure type attached

The neighboring P0390 code identifies the bank 2 exhaust cam circuit more generally. P0394 adds the intermittent category, while cam timing command-response faults belong to a different monitor family. The code does not itself establish a stuck phaser or quantify a slipped timing drive.

Preserve the complete DTC, crank/cam synchronization evidence and the exhaust-channel identity before choosing a circuit procedure. Verification should demonstrate consistent event placement while the monitor operates. The cited summary does not assign a physical sensor location, voltage specification or replacement part; those decisions depend on the engine-specific wiring and waveform information and the actual observed failure.

Source and applicability

This explanation covers the cited Ford monitor variants, not every vehicle displaying this code. Match the engine, sensor architecture and calibration before applying numerical limits.

Ford OBD summary, PDF page 132.