P0336

P0336 means the CKP signal is present but the tooth pattern the ECM sees does not match what it expects — typically a missing tooth, an extra tooth, or signal amplitude that drifts below the threshold during a specific RPM window. This is almost never a dead sensor; it is a mechanical or signal-integrity problem. Cheapest-first ladder: scope the CKP signal across the full RPM range and count teeth against the engine's tone-wheel spec (most domestic V8s are 58X, GM small block is 24X, modern Euro is 60-2). Look for one waveform that is shorter or taller than its neighbors — that is your damaged tooth. Inspect the reluctor ring through the sensor hole with a borescope for chipped, bent, or magnetized teeth (a magnetized tooth from a dropped tool will read as an extra pulse). Check sensor-to-reluctor air gap with a feeler gauge where adjustable (spec is typically 0.020-0.050 inch). Verify the crank pulley/harmonic balancer has not slipped on its rubber isolator — a balancer that has walked 5-10 degrees will throw P0336 with a perfectly good sensor. The expensive misdiagnosis is replacing the sensor twice and a PCM before realizing the flexplate has a hairline crack at one of the reluctor teeth.

Vehicle-specific patterns: GM 3.6L LY7 and LLT (2008-2013 CTS, SRX, Traverse) set P0336 alongside P0008/P0017 cam correlation codes when timing chain stretch lets the crank-to-cam relationship drift past 5 crankshaft degrees — the fix is a full timing kit, not a sensor. Chrysler 3.6 Pentastar (2011-2016 Wrangler, Grand Cherokee, 300) throws P0336 intermittently when the oil control valve screens clog and cam phasers can no longer hold commanded position, corrupting the crank correlation math. Ford 4.6/5.4 2V (1997-2004 Expedition, Crown Vic) shows P0336 from a cracked flexplate at the reluctor teeth — common on high-mileage trucks pulling trailers. VW/Audi 2.0T EA888 (2008-2014 GTI, A4, Tiguan) sets P0336 when the timing chain tensioner fails and the chain jumps a tooth — catch this fast or the pistons meet the valves. Estimated repair: $150 to $2200.