Ram Cummins · Crankshaft Position Sensor CircuitHigh

Ram Cummins P0336: Crankshaft Position Sensor Range/Performance

P-Code P0336 (FMI N/A) — Crankshaft Position Sensor "A" Circuit Range/Performance

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Quick Answer

P0336 means the Ram 6.7L Cummins crankshaft position sensor signal is present but out of the expected range or pattern. It's a High severity fault causing intermittent rough running or hesitation, distinct from a complete signal loss.

Overview: Ram Cummins P-Code P0336

P0336 differs from a total signal loss code like P0335 in that the crankshaft sensor is still sending something to the PCM, just not a clean, reliable signal within expected parameters. ProfessionalDieselRepair.com sees this most often after front engine service work where the sensor air gap wasn't properly set on reassembly, which is a quick and easy thing to verify before assuming the sensor itself has failed.

Repair Snapshot

Time

1 - 2.5 Hours

Difficulty

Intermediate

Parts Cost

$70 - $220

Dealer Labor

$350+

Tools Required

  • Cummins INSITE
  • Multimeter
  • Feeler Gauge
  • Snap-on NEXIQ

What P-Code P0336 Means

P0336 means the crankshaft position sensor signal on the Ram 6.7L Cummins is present but doesn't fall within the expected range or pattern, distinct from a total signal loss. This can cause intermittent misfire, hesitation, or rough running as the PCM struggles to accurately time injection events with unreliable position data. The MIL illuminates and symptoms are often intermittent rather than constant.

Symptoms Drivers Notice

  • Intermittent rough running or hesitation
  • MIL illuminated
  • Occasional hard starting
  • Possible random misfire codes accompanying this fault

Most Likely Root Causes

Incorrect sensor air gap after service

Common

If the sensor wasn't properly positioned after a timing cover or front engine repair, the air gap can be out of spec, producing a weak or distorted signal.

Chafed crank sensor harness

Common

Engine vibration wears the harness against nearby components, introducing intermittent noise into an otherwise present signal.

Degrading crank sensor

Occasional

Internal sensor degradation, often heat-related, causes a signal that's present but doesn't meet expected quality parameters, especially at operating temperature.

Damaged reluctor wheel teeth

Rare

Physical damage to the toothed wheel the sensor reads creates a genuinely irregular signal pattern independent of the sensor or wiring condition.

Common Misdiagnoses (Don't Waste Parts)

Replacing the sensor without checking the air gap

Why it happens: It's a fast parts-cannon fix that overlooks the simple mechanical adjustment that often resolves this fault.

Do this instead: Always verify the air gap with a feeler gauge against spec before and after any sensor replacement or timing cover work.

Assuming intermittent hesitation is a fuel delivery problem

Why it happens: Hesitation symptoms are commonly blamed on fuel system components without checking timing sensor signal quality first.

Do this instead: Always scan for stored codes before chasing fuel delivery components, since a marginal crank signal produces very similar symptoms.

Overlooking a recent timing cover or front engine repair as the cause

Why it happens: Techs don't always connect a fault code appearing shortly after unrelated front engine service to that recent work.

Do this instead: Always ask about recent service history and check air gap specifically if this code appears after any front engine or timing cover work.

Master Tech Commentary

Mechanic's Notes

Shop tip from ProfessionalDieselRepair.com: if this code shows up after any front engine or timing cover service, check the sensor air gap before anything else. An improperly set gap after reassembly produces this exact range/performance fault even with a perfectly good sensor.

Step-by-Step Diagnostic Procedure

  1. Step 1: Scan for codes with Cummins INSITE or a comparable tool and check freeze-frame data for when the fault occurred, noting engine temperature and RPM.
  2. Step 2: Inspect the crankshaft position sensor connector for corrosion or a loose fit, and verify the sensor is properly seated against its mounting boss.
  3. Step 3: Check the sensor's air gap with a feeler gauge if the sensor was recently serviced or if timing cover work has been performed.
  4. Step 4: Unplug the sensor and measure resistance across its terminals with a multimeter, comparing to spec for your engine.
  5. Step 5: Inspect the wiring harness from the sensor back to the PCM for chafing, then clear codes and road test while monitoring live signal quality.

Live Data & Freeze-Frame Tips

On INSITE, watch the engine speed signal quality parameter if your PCM calibration supports it, and note any correlation with recent service history or engine temperature. A scope on the sensor signal, if available, shows a distorted or inconsistent pattern versus a clean, healthy signal.

Safety Warnings

  • Never work near the crankshaft pulley or timing cover with the engine running.
  • Allow the engine to cool fully before accessing sensors near the timing case.
  • Disconnect the batteries before removing or adjusting the crank sensor.
  • Use proper lifting equipment if front engine covers must be removed for access.

When to Limp In vs Tow

Towing is rarely necessary since symptoms are usually intermittent rather than a complete stall. Consider towing only if the engine begins stalling repeatedly and will not reliably restart.

Prevention Tips for Fleets & Owner-Operators

  • Always verify crank sensor air gap with a feeler gauge any time the sensor or timing cover is disturbed.
  • Route the crank sensor harness away from vibration-prone brackets during any front engine service.
  • Inspect the sensor connector for corrosion at regular PM intervals.
  • Replace aging sensors proactively on high-mileage trucks showing early signs of intermittent hesitation.

Related Fault Codes

P0335

Crankshaft position sensor circuit malfunction, indicating a more complete signal loss than this range/performance fault.

P0340

Camshaft position sensor circuit malfunction, a related timing sensor the PCM cross-checks against this one.

P0016

Crankshaft/camshaft position correlation fault, worth checking if both timing sensors show related discrepancies.

Frequently Asked Questions

Can I drive with P0336 active?

You can drive, but expect the possibility of intermittent hesitation or rough running since the crank signal quality is degraded rather than completely lost.

How do I reset this code without a scanner?

Correcting the air gap or repairing any wiring issue and cycling the key may allow the code to self-clear, but a scan tool confirms the fault has fully resolved.

What triggers the derate on this code?

This fault doesn't typically trigger an emissions-style derate; the main risk is intermittent rough running rather than a gradual power limitation.

Is a crank sensor expensive to replace?

The part itself is usually inexpensive, often under $150, but labor varies depending on how accessible the sensor is on your specific engine.

Why did this code appear after I had timing cover work done?

The sensor air gap is a precise mechanical spec that needs to be verified after any front engine or timing cover service - an incorrect gap produces exactly this kind of range/performance fault.

Can a bad ground cause this code?

Yes, a poor sensor ground connection can introduce the same kind of degraded, out-of-range signal as a failing sensor or chafed signal wire.