P3892moderate severityPowertrain
Exhaust Gas Temperature Sensor Rationality - Post Aftertreatment
on 2012 Audi A3 2.0L TDI I4 · FWD
What this code means
The exhaust gas temperature sensor after the aftertreatment system shows readings that do not correlate with upstream sensors and engine operating conditions.
Symptoms
- Check Engine Light
- Incorrect aftertreatment temperature monitoring
- DPF regen timing affected
- False overtemperature warnings
- Aftertreatment protection mode may activate incorrectly
Common causes
- EGT sensor drift
- Sensor contaminated with soot
- Wiring resistance increased
- Sensor response time degraded
- Exhaust leak affecting sensor reading
Diagnostic steps
- Compare pre and post aftertreatment EGT readings
- Test EGT sensor response time
- Measure sensor resistance at known temperature
- Inspect sensor for soot contamination
- Check for exhaust leaks near sensor
Repair notes
Replace exhaust gas temperature sensor. Clean sensor bung of soot buildup. Verify temperature readings correlate after replacement.
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