What Does P0172 Mean on Your 2020 Dodge Charger?
A P0172 code on your 2020 Dodge Charger means the powertrain control module has detected an overly rich fuel mixture on Bank 1. The 2020 Charger is available with the 3.6L Pentastar V6 (292 hp), the 5.7L HEMI V8 (370 hp), or the 6.4L 392 HEMI V8 (485 hp). On V-configuration engines, Bank 1 is typically the driver's side cylinder bank.
Whether you have the V6 or one of the HEMI V8s, a rich condition wastes fuel, hurts performance, and can damage your catalytic converter over time. Getting it diagnosed quickly saves money and keeps your Charger running at peak performance.
Symptoms You Might Notice
- Check engine light on
- Reduced fuel economy
- Rough or unsteady idle
- Black smoke from the exhaust, especially on the HEMI
- Strong fuel smell from the tailpipe
- Slight hesitation or stumble under acceleration
Common Causes of P0172 on the 2020 Dodge Charger
- Dirty MAF Sensor — Both the Pentastar and HEMI engines use MAF sensors that can get contaminated over time. A dirty MAF underestimates airflow, causing the PCM to add excess fuel.
- Stuck-Open EVAP Purge Valve — A well-known Mopar issue. The purge solenoid sticks open and allows fuel vapors to continuously enter the intake.
- Failing O2 Sensor (Bank 1, Sensor 1) — A degraded upstream oxygen sensor provides inaccurate exhaust readings.
- Leaking Fuel Injector — Injectors on the HEMI's MDS (Multi-Displacement System) cylinders are particularly prone to leaking due to thermal cycling.
How to Diagnose the Problem
- Read all DTCs — Check for P0175 (Bank 2 rich), MAF codes, or EVAP codes.
- Compare fuel trims between banks — Both banks rich = MAF or purge valve. Bank 1 only = localized sensor or injector issue.
- Test MAF sensor — Verify readings against FCA specs for your engine at idle and 2,500 RPM.
- Test purge valve — Command open/close with a scan tool to verify sealing.
- Monitor O2 sensor — Check Bank 1 Sensor 1 voltage switching and response speed.
- Check fuel pressure and injectors — Verify system pressure and test individual injectors.
Repair Options and Cost Estimates
- MAF Sensor Cleaning — DIY: $10-$15. Shop: $55-$110.
- MAF Sensor Replacement — Parts: $70-$175, labor: $55-$110. Total: $125-$285.
- Purge Valve Replacement — Parts: $25-$60, labor: $55-$110. Total: $80-$170.
- O2 Sensor Replacement — Parts: $70-$185, labor: $90-$170. Total: $160-$355.
- Fuel Injector Replacement — Parts: $45-$140 each, labor: $180-$380. Total: $225-$520.
Can You Fix This Yourself?
MAF sensor cleaning and purge valve replacement are easy DIY tasks on the Charger. The MAF is in the air intake and the purge valve is accessible on top of the engine. O2 sensor replacement is moderate difficulty — you'll need to get under the car. Injector work on the HEMI is more involved and usually best for experienced mechanics.
Prevention Tips
- Replace the air filter on schedule
- Use quality fuel — the HEMI benefits from premium in higher-performance trims
- Monitor your fuel economy for sudden changes
- Follow Dodge's recommended maintenance intervals