P2388 moderate

Exhaust Gas Recirculation Sensor B Circuit Low

The P2388 code means the vehicle's onboard diagnostic system has detected: Exhaust Gas Recirculation Sensor B Circuit Low. This is a moderate severity code.

My Garage →
Keep driving?
Short distances only
DIY difficulty
moderate
Estimated cost
$150 - $450 (parts and labor)
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Common Symptoms

  • Check Engine Light on
  • Rough idle or engine hesitation
  • Increased NOx emissions
  • Engine pinging or knocking under load
  • Reduced fuel economy

Probable Causes (Ranked by Likelihood)

  • Short to ground in EGR sensor B circuit Very High
  • Faulty EGR position sensor High
  • Corroded sensor connector Moderate
  • PCM input circuit failure Low

Step-by-Step Diagnostic Procedure

  1. Scan for P2388 and review freeze frame conditions

  2. Inspect EGR valve for carbon buildup and free movement

  3. Test EGR sensor B signal voltage and compare to specifications

  4. Check EGR passage and tube for blockage or restriction

Frequently Asked Questions

What does P2388 mean?

P2388 indicates an EGR (Exhaust Gas Recirculation) system issue: Exhaust Gas Recirculation Sensor B Circuit Low. The EGR system reduces nitrogen oxide emissions by recirculating a portion of exhaust gas back into the intake.

Can I drive with P2388?

You can drive short distances. The engine may run rough or ping under load, and emissions will be higher than normal. Schedule a repair soon.

How much does it cost to fix P2388?

Most EGR repairs cost $150 to $450. Cleaning the valve may be sufficient ($100-$200), while a full replacement runs $200-$450.

Sources

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

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