Engine

P0376 — Timing Reference High Resolution Signal B Too Many Pulses

Severity: medium Drive with care, to a shop

What P0376 means

The engine control module compares the high-resolution timing reference signal (channel B) from the crankshaft or camshaft position sensor with the pulse count it expects. When more pulses arrive than should, it sets P0376. Electrical noise, a poor connection or a damaged tone ring are common reasons, and they can throw off the module's read of shaft position, spark and fuel timing.

Symptoms

  • Check Engine light on
  • Rough idle
  • Misfires or hesitation
  • Loss of power
  • Stalling
  • Hard starting or no-start

Possible causes

  1. Damaged wiring or connector at the sensor: open, corrosion or chafed harness
  2. Electrical noise picked up by the signal wire from poor shielding or nearby high-current wiring
  3. Faulty crankshaft or camshaft position sensor (channel B)
  4. Damaged or dirty tone ring (reluctor wheel)
  5. Timing belt or chain stretch or misalignment
  6. Failed engine control module (rare)

How to diagnose

  1. Scan all codes and freeze-frame data, noting any related crank or cam sensor codes
  2. Inspect the harness and connectors for chafing, oil, moisture and corroded pins
  3. Check sensor power, ground and signal wire shielding
  4. Inspect the sensor for metal debris or contamination and check its air gap to the wheel
  5. Inspect the tone ring for cracks, bent or extra teeth, or damage
  6. Use a scope to compare the sensor waveform to a known good pattern and look for extra pulses or noise
  7. Verify timing marks and cam-to-crank correlation, and check for belt or chain slack
  8. If everything else checks out, test the control module and look for software updates

Common fixes

  • Repair or replace damaged wiring and connectors
  • Replace the position sensor (channel B)
  • Replace a damaged tone ring or worn timing components
  • Restore shielding and reroute signal wires away from high-current lines
  • Replace or reflash the control module if confirmed faulty

Questions and answers

What does P0376 mean?

The engine computer is receiving more pulses than expected from the high-resolution timing signal B of a crank or cam position sensor. Wiring, the sensor or the tone ring are the usual culprits.

Can I drive with P0376?

Only briefly, such as to a repair shop. Misfires and sudden stalling are possible, and stalling in traffic is dangerous.

What should I check first?

Start with the sensor connector and wiring, then the sensor and tone ring. Replacing the control module should be the last step.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.