P0172
System Too Rich
Description
System too Rich (Bank 1) This body system diagnostic trouble code indicates an issue with the vehicle's comfort, safety, or convenience systems.
OBD Codes Details
Possible Causes
Blown fuse, faulty switch, damaged wiring harness, poor electrical connection
Solution
Check fuses and relays, inspect wiring harness, test switches and sensors, repair damaged circuits
Symptoms
- Black smoke from the exhaust
- Strong fuel or sulfur smell from exhaust
- Rough idle
- Poor fuel economy
- Check engine light illuminated
Diagnostic Recommendations
- Check fuel pressure regulator for leaks
- Inspect MAF sensor for contamination or damage
- Test O2 sensors for correct rich/lean response
- Check for a clogged air filter restricting airflow
- Inspect fuel injectors for leaking or stuck-open condition
Repair Cost Estimate
- Fuel pressure regulator replacement: $100-250
- MAF sensor cleaning/replacement: $50-400
- O2 sensor replacement: $150-400
- Fuel injector cleaning/replacement: $200-800
- Total diagnostic and repair: $200-1500
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Fact-checking completed
Verified by:
Pavel Volkov
Created:
Last updated:
Information verified against official sources
Official Sources
Society of Automotive Engineers
Official OBD-II diagnostic trouble codes standard (SAE J2012)
Automotive engineering standards organization
International Organization for Standardization
International standard for vehicle diagnostic systems
International standards for automotive diagnostics
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