Crankshaft Position Sensor Failure

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The crankshaft position sensor (CKP) reads engine speed and position from a tone wheel on the flywheel/flexplate; when it fails or receives a distorted signal, the T1N may crank without starting, stall while driving, or throw a P0336 fault. Both a failed sensor and a bent tone-wheel tooth can produce identical symptoms.

Symptoms

Engine cranks but will not start, or starts then immediately dies [1, 2]
Tachometer does not move while cranking — a key indicator of no CKP signal [2]
Extended cranking before the engine catches [1]
Intermittent stalling while driving, with the engine restarting after a cool-down period of an hour or so [3]
Fault code P0336 (crankshaft position sensor range/performance) stored in the ECU [6]
Engine refuses to rev freely; fault code 2045-2 associated with a bent tone-wheel tooth [9]

Causes

Failed crankshaft position sensor — the sensor itself wears out or loses signal output [0, 1]
One or more bent pickup teeth on the flywheel/flexplate tone wheel, which distorts the signal even with a good sensor [1, 9]
Flywheel or flexplate physically contacting and scratching the sensor, causing damage or incorrect air gap [6]
Fuel delivery issues that mimic CKP symptoms (air in fuel lines can also cause a non-moving tach/no-start) [2]

Diagnosis

Check whether the tachometer needle moves while cranking — a completely stationary tach with the engine cranking strongly suggests no CKP signal is reaching the ECU [2]
Scan for fault codes; P0336 points directly to crankshaft position sensor range or performance, and code 2045-2 is associated with a bent tone-wheel tooth [6, 9]
Inspect the flywheel/flexplate tone-wheel teeth through the sensor bore or starter opening for any bent or damaged teeth — even one bent tooth can cause the fault [1, 9]
Compare the length of the replacement sensor against the old one before installing to ensure correct protrusion and air gap [6]
Check whether the flywheel or flexplate is contacting (scratching) the sensor face, which indicates misalignment or incorrect sensor depth [6]
Rule out fuel-system air ingestion first, especially if a fuel filter was recently changed — air in the lines can also prevent starting and cause a non-moving tach [2]

Repair

Replacing the crankshaft position sensor is a straightforward bolt-on job accessible from the engine block. The bigger challenge is diagnosing whether the sensor itself is bad or whether bent tone-wheel teeth are the root cause — replacing the sensor without inspecting the tone wheel will not fix a tooth problem. If teeth are bent, they must be carefully restored; a damaged flexplate may require professional attention. Most mechanically inclined owners can handle the sensor swap themselves.

Read first

If the flywheel or flexplate is physically contacting the sensor, do not simply swap the sensor — the underlying misalignment must be corrected first to avoid damaging the replacement [6].
If the driveshaft is removed for access, mark its orientation on the transmission flange before removal; installing it in the wrong position causes driveline vibration [5].

Tools

OBD-II scan tool capable of reading Mercedes/Sprinter fault codes (P0336, 2045-2)
Basic socket set and wrenches (sensor retaining nut/bolt)
Flashlight or inspection mirror (tone-wheel tooth inspection)
Pick or small flat tool (careful tooth restoration if bent)

Steps

Confirm the fault before replacing parts: scan for P0336 or 2045-2 and verify the tachometer does not move while cranking [2, 6, 9].
Locate the crankshaft position sensor on the engine block; disconnect the electrical connector.
Remove the single retaining nut/bolt securing the sensor to the engine block. Torque spec for reinstallation: 8 N·m (70 in·lb) [4].
Before installing the new sensor, compare its length to the old one to ensure the correct air gap from the tone wheel [6].
Inspect the flywheel/flexplate tone-wheel teeth through the sensor bore for bent or damaged teeth. If a bent tooth is found, carefully restore it — one bent tooth is sufficient to cause the fault and will not be fixed by sensor replacement alone [1, 9].
Check that the flywheel/flexplate is not contacting or scratching the sensor face; if it is, investigate the source of misalignment before proceeding [6].
Install the new sensor, torque the retaining nut/bolt to 8 N·m (70 in·lb), and reconnect the electrical connector [4].
Clear fault codes, start the engine, and confirm the tachometer responds normally and no codes return [2, 6].
After reinstalling any driveshaft removed for access, note that driveshaft orientation matters — mark position before removal to avoid reassembly vibration [5].

Torque specs

Crankshaft position sensor nut/bolt to engine block: 8 N·m (70 in·lb) [4]

Parts

Plain part names — affiliate links and pricing are coming in a later update.

Crankshaft position sensor (verify length matches OEM specification before installing)

Related forum threads

19 ↳2003 strange cold no start
19 ↳06 Starts then dies
19 ↳'03 Stalling while driving or no start
19 ↳Crankshaft Position Sensor Failure?
17 ↳Crankshaft position sensor P0336

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Generated 5/4/2026 · claude-sonnet-4-6