2023 Toyota Corolla: Engine complaints
Owner-reported issue (NHTSA complaints, not a recall)
Symptoms
NHTSA has 13 owner complaints for the 2023 Toyota Corolla that list the engine component. Complaints are individual owner reports, not verified defects.
Examples:
- NHTSA complaint ODI #11706705 (filed 12/23/2025): “After fueling strong fuel smell in vehicle within 100 miles check fuel cap light came on. next day check engine light came on. made appointment at dealership . dealership performed evap smoke test which found smoke coming from top of fuel cell. installed fuel pump ring and evap hose clip. performed …”
- NHTSA complaint ODI #11695545 (filed 10/25/2025): “I got a message that the engine needs maintenance and i should go to the dealership and have the coolant bypass valve repaired. i see there's a lawsuit against toyota for a manufacturing defect in that component on 2019-2023 corollas. i'd like to know if i'll get a refund.…”
- NHTSA complaint ODI #11695043 (filed 10/22/2025): “A message came out that i need to maintain the engine and take it to the concierge and they told me that it is the coolant by pass valve…”
Likely causes
These complaints do not establish a single root cause; read the examples above and get a diagnosis.
Fix, in plain English
No single fix is established by these reports. Check your VIN for open recalls at nhtsa.gov/recalls, ask a dealer about technical service bulletins (TSBs) or extended warranty coverage, then have the system diagnosed.
DIY difficulty: Pro
Internal engine work (lifters, oil consumption, fuel dilution diagnosis) requires engine teardown or dealer software/tests. (Our assessment.)
Cost
No sourced cost range for this issue. Get a written quote after diagnosis.
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