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.
- 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
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.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
-
Scan for P2388 and review freeze frame conditions
-
Inspect EGR valve for carbon buildup and free movement
-
Test EGR sensor B signal voltage and compare to specifications
-
Check EGR passage and tube for blockage or restriction
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
- 2015-2023 Ford F-150 5.0L V8
- 2013-2021 Hyundai Sonata 2.0L Turbo I4
- 2009-2017 BMW 328i 3.0L I6
- 2011-2017 Chevrolet Silverado 1500 5.3L V8
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