P0742high severityPowertrain
Torque Converter Clutch Circuit Stuck On
on 1998 Audi A8 4.2L V8 · AWD
What this code means
The TCC is not releasing when it should, causing the engine to stall or shudder at low speeds.
Symptoms
- Stalling when coming to a stop
- Shudder at low speed
- Vehicle lunging at stops
- Check Engine Light
Common causes
- TCC solenoid stuck on
- Valve body issue
- Wiring short keeping solenoid energized
Diagnostic steps
- Monitor TCC engagement state
- Test solenoid
- Check valve body
- Check wiring for shorts
Repair notes
Replace TCC solenoid. Driving with TCC stuck on causes stalling.
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