Powertrain
generic / SAE
P20F5
Reductant Consumption Too High
The DEF consumption observed over the dosing window is above the model expectation — typically a leaking injector seat, leaking line fitting, or a pressure-control valve that vents constantly to the tank.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number– / F5
Possible causes
- Injector seat leaks DEF into exhaust high
- Cracked line or fitting medium
Symptoms
- Check engine light or NOx warning on
- AdBlue/DEF level or quality warning
- Possible no-start countdown after ignore period
- Failed emissions inspection (NOx)
Inspection / repair
- Difficulty: hard
- DIY: shop recommended
- Estimated cost: 200–1500 €
- Estimated time: 1–4 h
- Component: reductant injection valve
- Component: reductant supply line
- Component: reductant pressure control valve
- MIL / check engine light
- emissions-relevant
Sources
References
sae:J2012