2020 Dodge Challenger Check Engine Light in Millbury, MA

It means the engine computer detected a fault and stored an OBD-II code identifying the affected system.

This warning can flag anything from a loose gas cap to an emissions or ignition issue on your 2020 Dodge Challenger. The onboard code guides proper diagnosis, but it doesn’t pinpoint the exact failed part. Our Millbury team reads live data and freeze-frame information to see what happened when the fault set, then tests components to verify the cause.

• Loose or faulty gas cap (EVAP)
• Misfire or ignition fault (flashing light)
• OBD-II code + data direct testing

The most common causes are O2 sensor faults, EVAP leaks, misfires, catalytic converter inefficiency, or MAF issues.

On a 5.7L HEMI V8, wear items like spark plugs and coils can trigger misfire codes, and temperature swings can reveal small EVAP leaks. An aging oxygen sensor may reduce fuel economy and set efficiency codes. We confirm the specific reason on your Challenger using OEM diagnostics and targeted tests before any repair is recommended.

• 5.7L HEMI: plug/coil misfire risk
• EVAP leaks after loose gas cap
• O2 sensor aging affects MPG

A steady light means drive cautiously to service, while a flashing light means stop driving due to a severe misfire risk.

A flashing light can quickly overheat and damage the catalytic converters on your 2020 Dodge Challenger. If the light is steady, avoid hard acceleration and schedule a prompt diagnosis in Millbury. Tightening the gas cap is a quick first step; if the light persists, let our technicians test the system and prevent costlier damage.

• Flashing = severe misfire; tow in
• Steady = limit load; book service
• Check gas cap, then scan

Parts stores provide a free OBD-II code read; dealer diagnostics use factory scan tools and pinpoint tests to find the root cause.

Codes have multiple potential causes, and guessing at parts can waste time and money. Our Millbury service center accesses Chrysler/Dodge proprietary data, technical service bulletins, and performs isolation testing that generic readers can’t. You’ll get a verified cause and a written estimate—plus you can review current service specials.

• OEM scan data and guided tests
• Smoke/scope tests as needed
• Written estimate before repair

No—clearing codes resets readiness monitors, and your Challenger may fail MA emissions until those monitors complete.

Massachusetts inspections check that OBD readiness monitors are set. After a reset, your 2020 Dodge Challenger needs a complete drive cycle to repopulate monitors, and an underlying fault can immediately reset the light. We can verify readiness and fix the root cause so your car is inspection-ready.

• Readiness must be complete
• Drive cycle may be required
• Fix fault before inspection

Expect a diagnostic fee of ${{vehicle.real_diagnostic_price_range_usd.min}}–${{vehicle.real_diagnostic_price_range_usd.max}} for a 2020 Dodge Challenger.

We provide up-front pricing in Millbury and perform a complete diagnosis with OEM tools; when applicable, the diagnostic fee is often credited toward the resulting repair. Your visit includes a code scan, data review, and targeted testing to confirm the exact cause. You can schedule an appointment and check service specials before you arrive.

• Factory scan + data review
• Isolation tests as needed
• Written estimate provided

Your 2020 Dodge Challenger benefits from a structured process that moves from code to confirmed cause. We start with an initial OBD-II scan and freeze-frame review to capture what the powertrain control module saw when the fault set. Next comes a visual and functional check of related systems—fuel, air, spark, and emissions—followed by targeted isolation testing as needed (EVAP smoke testing, ignition scope patterns, voltage drop, and pin-out checks). Live-data road testing validates repairs before we finalize a written estimate. No parts are replaced without authorization. When you’re ready, use our online schedule service tool to pick a time that works for you.

Welcome to Herb Chambers Chrysler Dodge Jeep RAM FIAT of Millbury, your premier multi-brand automotive destination in Central Massachusetts. Proudly serving Worcester County and the surrounding communities—including Worcester, Auburn, Grafton, Shrewsbury, Sutton, and Oxford—we provide a first-class car-buying and ownership experience. For your 2020 Dodge Challenger, our factory-authorized service center blends OEM scan capability with real-world testing that generic code readers can’t match. New England’s temperature swings can expose small EVAP leaks, and cold starts may surface fuel or ignition issues—our technicians use guided diagnostics and Chrysler/Dodge service information to verify the root cause. You’ll find us at 2 Latti Farm Road (off Route 20), Millbury, MA 01527. Have questions or ready to book? Use our schedule appointment link for quick online booking.

Several OBD-II codes commonly appear on the 2020 Dodge Challenger and point to systems that need confirmation testing. P0300–P0308 typically indicate random or cylinder-specific misfires; on a 5.7L HEMI V8, worn spark plugs or a weak coil can trigger these. P0440–P0456 relate to EVAP system leaks, often from a loose or failing gas cap or a small leak revealed by temperature changes. P0133 or P0153 suggest slow O2 sensor response, while P0420 signals catalyst efficiency below threshold. Ignoring misfire or efficiency codes can overheat and damage catalytic converters, increasing repair costs significantly. Bring your 2020 Dodge Challenger to Herb Chambers Chrysler Dodge Jeep RAM FIAT of Millbury in Millbury for an accurate diagnosis — schedule service.