P0420 and catalyst efficiency codes: notes for Greater Houston heat waves
FlexFix Team
# P0420 and catalyst efficiency codes: notes for Greater Houston heat waves If it is safe to drive, we still want a documented test plan before major work. A **$60 mobile diagnostic** buys a professional assessment; **if you approve the repair, that fee applies toward labor** on that job. Still driving? **Note any new noises, smells, or lights**; small details narrow the path fast. _Educational overview only—not a remote diagnosis of your vehicle. Estimates depend on inspection and your approval._