P0100 on Your 2023 Toyota Prius
A P0100 code on your 2023 Toyota Prius indicates the ECM has detected a malfunction in the mass air flow (MAF) sensor circuit. Your completely redesigned 5th-generation Prius features the new 2.0L hybrid powertrain—a significant upgrade from the previous 1.8L—and this code is relatively uncommon on a newer vehicle.
Symptoms
- Check engine light on
- Rough idle when gas engine runs
- Hesitation during acceleration
- Reduced fuel economy
- More frequent gas engine engagement
- Possible stalling
Common Causes on the New Prius
- Contaminated MAF sensor (30%) — Oil or debris from manufacturing or early service.
- MAF connector issue (25%) — Connection not fully seated or vibrated loose.
- Faulty MAF sensor (20%) — Factory-defective sensor.
- Software calibration (12%) — New powertrain may need ECM software refinement.
- Intake assembly issue (8%) — Loose clamp or boot.
- Wiring defect (5%) — Manufacturing issue.
What to Do
- Toyota dealer visit — Warranty repair at no cost.
- Document symptoms — Note when and how the issue occurs.
- Don't clear the code — Dealer needs freeze frame data.
Repair Costs
- Under warranty: $0
- MAF cleaning (if out of warranty): $10–$15 (DIY)
- MAF sensor: $125–$295
Warranty
Your 2023 Prius is covered under Toyota's 3-year/36,000-mile warranty through 2026 and the federal emissions warranty for 8 years/80,000 miles through 2031.