What will your check engine code cost?
Repair cost ranges built from reader-shared invoices (early estimates for now), plain-English meanings, and honest AI scan tool comparisons.
Most-searched codes
P0420
Catalyst System Efficiency Below Threshold (Bank 1)P0300
Random/Multiple Cylinder Misfire DetectedP0171
System Too Lean (Bank 1)P0455
Evaporative Emission System Leak Detected (Large Leak)P0128
Coolant Thermostat (Coolant Temp Below Thermostat Regulating Temperature)P0442
Evaporative Emission System Leak Detected (Small Leak)
Catalyst System Efficiency Below Threshold (Bank 1)P0300
Random/Multiple Cylinder Misfire DetectedP0171
System Too Lean (Bank 1)P0455
Evaporative Emission System Leak Detected (Large Leak)P0128
Coolant Thermostat (Coolant Temp Below Thermostat Regulating Temperature)P0442
Evaporative Emission System Leak Detected (Small Leak)
Compare AI scan tools
ScanFixAI
Pro $29.99/mo or $249.99/yr
Pro $29.99/mo or $249.99/yr
OBDAI
Annual PRO bundle $299
Annual PRO bundle $299
BlueDriver Pro Next-Gen
$119.95 list ($99.95 sale seen)
$119.95 list ($99.95 sale seen)
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