Engine codes keeps coming back?

2013 TOYOTA COROLLA
163,000 MILES • 1.8L • MANUAL
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RLPETERSON78
  • MEMBER
  • 146 POSTS
My car started with a lot of codes, P0101, P043E, P043F, P02401 and P4202. I have checked all the wires, fuses, Mass airflow sensor, purge valve and leak pump and they had no faults. I replaced all the grounds and that seemed to solved the problem. I drove it for three days and the engine light came back on. The Code is P0101, but the Mass airflow sensor is fine. What am I missing?
Jul 13, 2026 at 8:04 AM
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RLPETERSON78
  • MEMBER
  • 146 POSTS
And I took it to Toyota dealership and my ECM is ok.
Jul 13, 2026 at 10:19 AM
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STRAILER
  • ✓Experienced Mechanic
  • 55,051 POSTS
So when you say the MAF is fine did you replace it or check the flow with a scanner? Also can you please double check the other code numbers, some of them don't match up. I would look at the air intake boot between the MAF and the throttle body as well. Please let me know so we can continue.
Jul 14, 2026 at 6:39 AM
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