P3833high severityPowertrain
DEF Dosing Valve Stuck Open
on 2010 Audi A3 2.0L TDI I4 · FWD
What this code means
The DEF dosing valve is stuck in the open position, causing excessive DEF injection into the exhaust.
Symptoms
- DEF consumption very high
- White exhaust smoke (DEF steam)
- Ammonia smell from exhaust
- DEF tank empties rapidly
- SCR system over-dosing
- Possible SCR catalyst damage from excess urea
Common causes
- Dosing valve stuck mechanically
- Solenoid energized continuously
- Control module error commanding open
- DEF pressure forcing valve open
- Valve return spring broken
Diagnostic steps
- Monitor DEF dosing rate vs commanded
- Check DEF consumption rate
- Test valve solenoid de-energized state
- Inspect valve for mechanical damage
- Read dosing module fault codes
Repair notes
Replace DEF dosing valve. Inspect SCR catalyst for ammonia slip or urea deposit damage.
🔌 Don't have a code reader?
Any of these will read and clear this code — pick by how deep you want to go.
Bluetooth code reader (~$25)
Veepeak OBDCheck BLE →
Pairs with your phone — reads and clears codes, live data.
Serious DIY (~$100)
BlueDriver Pro →
Enhanced codes (ABS, airbag, TPMS) plus repair reports.
Shop-grade tablet (~$300+)
Autel MaxiCOM MK808S →
Bidirectional tests, service resets, all systems.
As an Amazon Associate, OLP earns from qualifying purchases — how we link. This never changes the specs we publish.
Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0011
Intake Camshaft Position Timing Over-Advanced Bank 1
P0012
Intake Camshaft Position Timing Over-Retarded Bank 1
P0013
Exhaust Camshaft Position Actuator Circuit/Open Bank 1
P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
Exhaust Camshaft Position Timing Over-Retarded Bank 1