Fuel Additive Tank
The small reservoir holding the catalytic additive dosed into the fuel on diesels using a fuel-borne catalyst, usually mounted beside or within the fuel tank. A consumable rather than a component that fails — it is emptied by ordinary use and refilled at a long service interval, and the common problem is simply that nobody knew it was there.
Beyond running empty, the faults it does have are the ordinary ones of a small dosing system: a pump that has stopped delivering, a blocked or leaking feed line, and additive that has settled or crystallised after very long periods without use. Its level is tracked by counting what has been dosed rather than by measuring what remains, so the counter must be reset whenever it is refilled — a refill without the reset leaves the warning in place and looks exactly like a refill that did not work.
Also known as: additive tank, eolys tank, additive reservoir, fap fluid tank, fuel borne catalyst tank
Referenced by 4 codes
Codes involving this component (4)
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
- Fuel Filler Cap 18
- 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
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