Investigating the P0100 Code on Your 2022 Lexus RX
A P0100 code on your 2022 Lexus RX indicates the ECM has detected a mass airflow (MAF) sensor circuit malfunction. The fifth-generation RX may feature the 2.4-liter turbocharged four-cylinder (RX 350) or the 2.5L hybrid powertrain (RX 350h/450h+), and all configurations need accurate MAF data. Lexus builds on Toyota's legendary reliability, but MAF issues can occur on any vehicle.
What P0100 Means
P0100 flags erratic, intermittent, or out-of-range MAF sensor signals. Lexus uses a hot-wire type MAF sensor that measures air mass rather than volume, providing more accurate readings across temperature and altitude changes. When this signal becomes unreliable, the ECM cannot properly manage fuel delivery.
Common Symptoms
- Check engine light on
- Rough or unsteady idle
- Reduced power and throttle response
- Poor fuel economy
- Hesitation during acceleration
- Hybrid models: possible EV mode limitations
Top Causes Ranked by Likelihood
- MAF sensor contamination (35-40%) — Oil vapor and debris on the hot-wire element
- Air filter issue (20-25%) — Dirty or improperly seated filter
- Intake air leak (15-20%) — Cracked boot or loose clamp; turbo model: charge pipe leak
- Connector or wiring fault (10-15%) — Corroded or loose MAF connection
- MAF sensor failure (10-15%) — Internal degradation
Warranty Status
Your 2022 RX is within Lexus's 4-year/50,000-mile basic warranty through 2026. The powertrain warranty extends to 6 years/70,000 miles through 2028. Federal emissions warranty: 8yr/80k through 2030. Contact your Lexus dealer for warranty service.
Estimated Repair Costs
- MAF sensor cleaning: $10-15 (DIY)
- MAF sensor replacement: $150-350 (OEM) + $80-150 (labor)