P2377 serious

Fuel Injection Pump Speed/Timing Sensor Circuit Low

The P2377 code means the vehicle's onboard diagnostic system has detected: Fuel Injection Pump Speed/Timing Sensor Circuit Low. This is a serious severity code.

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Keep driving?
Short distances only
DIY difficulty
hard
Estimated cost
$300 - $1,500 (parts and labor)
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Common Symptoms

  • Check Engine Light on
  • Engine hard starting or no start condition
  • Rough idle and engine knocking
  • Excessive smoke from exhaust
  • Significant power loss

Probable Causes (Ranked by Likelihood)

  • Short to ground in pump timing/speed sensor wiring Very High
  • Faulty fuel injection pump sensor High
  • Corroded sensor connector Moderate
  • PCM driver circuit failure Low

Frequently Asked Questions

What does P2377 mean?

P2377 relates to the fuel injection pump system: Fuel Injection Pump Speed/Timing Sensor Circuit Low. This code is most commonly seen on diesel vehicles where precise pump timing is critical.

Can I drive with P2377?

Drive only short distances to a shop. Fuel injection pump issues can cause hard starting, poor performance, and potential engine damage from incorrect timing.

How much does it cost to fix P2377?

Costs range from $300 for sensor or wiring repairs to $1,500+ if the injection pump itself needs replacement or rebuilding.

Mechanics Guide Step-by-step diagnosis

Step-by-Step Diagnostic Procedure

  1. Retrieve P2377 and check for related fuel system codes

  2. Monitor injection pump timing and speed data with a scan tool

  3. Inspect injection pump sensor wiring and connectors for damage

  4. Verify injection pump timing alignment marks are correct

Sources 1

This page is built from documented references. Verify against your own service info before repair work.

  • SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)

Commonly Affected Vehicles

  • 2010-2018 Volkswagen Jetta 2.0L I4
  • 2010-2020 Volkswagen Jetta 1.4L Turbo I4
  • 2011-2017 Ford F-150 5.0L V8
  • 2012-2020 BMW 328i 3.0L I6

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