P0370

P0370 is timing reference high-resolution signal A malfunction — this refers to the high-resolution crank position signal used by the ECM for precision ignition timing and misfire detection, distinct from the basic crank signal used for engine speed. On engines equipped with both a coarse-resolution and high-resolution crank sensor (common on Nissan VQ-series, some GM and Mitsubishi platforms), this code targets the high-res sensor specifically. Diagnostic ladder: scope the high-resolution signal — it should produce many pulses per crank revolution (typically 60-1 or 120-2 patterns) with consistent amplitude and timing. Inspect the sensor mounting (a loose sensor or worn locator pin lets the air gap drift, producing weak or missing pulses), the reluctor ring or tone wheel for damaged teeth, and the sensor connector for oil intrusion. Caveat: P0370 sometimes coexists with P0335 or P0336 — if both log together, focus on the wiring and ECM connector rather than two simultaneous sensor failures.

Vehicle-specific patterns: Nissan VQ35DE V6 (Maxima, Altima, 350Z, Murano, Pathfinder, 2002-2008) — high-resolution CKP sensor on the bellhousing fails from heat-soak; sensor is $80-130. Mitsubishi 4G63T (Evo VIII/IX, 2003-2007) — crank angle sensor in the distributor housing fails from oil contamination; distributor o-ring leak is the upstream cause, replace o-ring and sensor together. GM Northstar 4.6L V8 (Cadillac Seville, Deville, 1996-2005) — crank sensor wear pattern combined with crank reluctor ring chip; verify reluctor before sensor replacement. Mazda RX-8 Renesis (2004-2011) — leading and trailing ignition timing signal corruption from oil contamination at the eccentric shaft sensor. Estimated repair: $90 to $620.