Fuel Filler Cap
Seals the top of the evaporative system, and by a wide margin the most common cause of evaporative leak codes — as well as the cheapest to eliminate. Its seal hardens with age, so a cap that tightens with the usual clicks can still leak, and a visual inspection is not sufficient to clear it. Always worth trying before paying for diagnosis.
Also known as: fuel cap, gas cap, petrol cap, filler cap, tank cap
Referenced by 18 codes
Codes involving this component (18)
- P2269 Water in Fuel Condition — Sensor A Stop driving High
- P2404 Evaporative Emission System Leak Detection Pump Sense Circuit Range/Performance Moderate
- P2422 Evaporative Emission System Vent Valve Stuck Closed Moderate
- P0440 Evaporative Emission System Malfunction Low
- P0442 Evaporative Emission System Leak Detected — Small Leak Low
- P0455 Evaporative Emission System Leak Detected — Large Leak Low
- P0456 Evaporative Emission System Leak Detected — Very Small Leak Low
- P0457 Evaporative Emission System Leak Detected — Fuel Cap Loose or Off Low
- P04EA Evaporative Emission System Small Leak Detected — Fuel Tank Side
- P04EC Evaporative Emission System Large Leak Detected — Fuel Tank Side Low
- P04EE Evaporative Emission System Very Small Leak Detected — Fuel Tank Side Low
- P04EF Evaporative Emission System Very Small Leak Detected — Fresh Air Side
- P0624 Fuel Cap Lamp Control Circuit Low
- P2408 Fuel Cap Sensor Switch Circuit Low
- P2409 Fuel Cap Sensor Switch Circuit Range/Performance Low
- P2410 Fuel Cap Sensor Switch Circuit Low Low
- P2411 Fuel Cap Sensor Switch Circuit High Low
- P2412 Fuel Cap Sensor/Switch Circuit Intermittent/Erratic Low
Other components in Exhaust and Emissions
- Oxygen Sensor 326
- EGR Valve 150
- Catalytic Converter 142
- NOx Sensor 118
- Reductant Injector 107
- Exhaust Gas Temperature Sensor 95
- Reductant Tank 95
- Diesel Particulate Filter 76
- SCR Catalyst 65
- EGR Cooler 62
- Exhaust Gas Differential Pressure Sensor 58
- Fuel Tank Pressure Sensor 58
- Exhaust Pressure Control Valve 56
- Reductant Heater 55
- Reductant Pump 51
- EVAP Vent Valve 43
- Exhaust Aftertreatment Fuel Injector 42
- Charcoal Canister 33
- EGR Position Sensor 32
- Secondary Air Injection Pump 32
- Reductant Temperature Sensor 29
- EVAP Leak Detection Pump 29
- EVAP Purge Valve 27
- Particulate Matter Sensor 24
- Reductant Control Module 24
- Reductant Level Sensor 23
- Secondary Air Switching Valve 22
- EGR Temperature Sensor 21
- Secondary Air Check Valve 21
- Catalyst Heater 20
- Catalyst Temperature Sensor 20
- EGR Cooler Bypass Valve 16
- Reductant Quality Sensor 16
- Exhaust Back Pressure Sensor 15
- Purge Flow Sensor 13
- Direct Ozone Reduction Catalyst 13
- EGR Vacuum Solenoid 9
- Fuel Vapour Temperature Sensor 5
- Fuel Additive Control Module 4
- Fuel Additive Tank 4
Information, not instruction
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