P0175 on the 2020 Dodge Challenger: Muscle Car Fuel System Diagnosis
The 2020 Dodge Challenger is an American muscle car icon, available with the 3.6L Pentastar V6 (305 hp), 5.7L HEMI V8 (375 hp R/T), 6.4L HEMI V8 (485 hp Scat Pack), or the supercharged 6.2L Hellcat (717-797 hp). All engines have a V-configuration with a true Bank 2. On the HEMI engines, Bank 2 is the passenger side (cylinders 2, 4, 6, 8). P0175 means the ECM has detected a persistent rich condition on Bank 2 that exceeds fuel trim correction limits.
At 4-6 years old with potentially 40,000-90,000 miles, the 2020 Challenger is entering the mileage range where sensor contamination and wear trigger fuel system codes. The Challenger's performance-oriented nature often means harder driving, which accelerates sensor aging.
How You'll Know
- Check engine light on the retro-styled gauge cluster
- Fuel economy dropping — HEMIs are already thirsty, and P0175 makes it worse
- Rough idle, especially noticeable with the HEMI's characteristic lope
- Strong fuel smell from the exhaust, particularly under hard acceleration
- Black soot on the wide exhaust tips
- MDS cylinder deactivation on the 5.7L may engage/disengage roughly
- Reduced acceleration — the Challenger should pull hard, and P0175 diminishes that
- Possible popping or backfiring on deceleration
What's Causing It in Your Muscle Car
1. MAF Sensor Contamination — High Likelihood
The Challenger's cold air intake draws significant volumes through the front-facing air scoop and past the MAF sensor. After 40,000+ miles of driving — especially spirited driving with frequent full-throttle pulls — the MAF sensor has accumulated contamination from PCV oil vapors and road debris. The HEMI V8s draw enormous air volumes, particularly the 6.4L and 6.2L, and MAF accuracy is critical for proper fuel delivery. On the 5.7L R/T, the MAF must also account for MDS cylinder transitions, adding complexity to accurate airflow measurement.
2. O2 Sensor Wear from High-Performance Use — Medium Likelihood
Challenger owners drive their cars hard. Drag launches, highway pulls, and spirited canyon driving generate extreme exhaust temperatures that accelerate O2 sensor aging. The 6.4L Scat Pack and Hellcat produce particularly high EGTs under full power. A worn Bank 2 O2 sensor that responds slowly or reads inaccurately causes the ECM to miscalculate fuel delivery, enriching the mixture beyond correction limits.
3. Fuel Injector Issues — Medium Likelihood
The HEMI engines use large multi-port fuel injectors designed for high fuel flow rates. The 6.4L's injectors handle over 30 lbs/hr each at full duty cycle. At 40,000-90,000 miles, injector seals can wear and pintles can develop carbon deposits from the combustion process. A leaking or over-delivering injector on Bank 2 enriches those cylinders. The Pentastar V6's direct injectors face different challenges — high-pressure carbon buildup on injector tips alters spray patterns.
4. Aftermarket Modifications — Low Likelihood
Many Challengers are modified with aftermarket cold air intakes, headers, exhaust systems, and ECU tunes. Any modification that alters the intake air path, exhaust flow, or fuel delivery calibration can cause P0175. Catless headers that relocate O2 sensors or cold air intakes that change MAF sensor housing diameter are common culprits. If you've modified your Challenger, consider reverting to stock temporarily to determine if the modification caused the code.
Diagnostic Approach for the Challenger
- Scan with a Chrysler/Stellantis-compatible scanner (wiTECH, alfaOBD)
- Note which engine you have — diagnostic approach varies
- Compare Bank 1 vs Bank 2 fuel trims at idle and 2,500 RPM
- Test MAF sensor against specifications for your engine size
- Monitor O2 sensor response times — compare banks
- Check for aftermarket modifications that may be causing the code
- Run fuel pressure and injector balance tests
Repair Costs
- MAF sensor: $80–$220
- O2 sensor: $100–$280
- Fuel injector (HEMI, each): $60–$180
- Fuel injector (Pentastar DI, each): $130–$350
- EVAP purge valve: $60–$150
DIY Muscle Car Wrenching
The Challenger is one of the most DIY-friendly performance cars. The engine bay is spacious, especially on HEMI models. MAF sensor replacement takes minutes. Spark plug replacement on the HEMI is straightforward with the dual-plug design (16 plugs total). O2 sensor access requires getting under the car and may involve heat-seized threads. Injector work on the HEMI is moderate difficulty with fuel rail removal. The Challenger enthusiast community — forums, YouTube channels, and Facebook groups — has extensive repair documentation.