16618/P0234/000564 - Boost Pressure Regulation: Limit Exceeded (Overboost Condition)
Possible Symptoms
Malfunction Indicator Light (MIL) ON
Boost Pressure too high
Reduced Power Output
Possible Causes
Hoses incorrectly connected, disconnected, blocked or leaking
Boost Pressure Control Valve (N75) faulty
Boost Pressure Sensor (G31) faulty
Turbo Charger stuck/faulty
Possible Solutions
Check Charge Pressure Control System
Perform Output Test (to check the Turbo Charger)
Perform Basic Setting (to check the Charge Pressure Control)
Perform Pressure Test to locate Leaks
Check/Replace Boost Pressure Control Valve (N75)
Check/Replace Boost Pressure Sensor (G31)
Check/Replace Turbo Charger
16396/P0012/000018 - Bank 1: Camshaft A (Intake): Advance Setpoint not Reached (Over-Retarded)
Possible Symptoms
Erratic Idle
Possible Causes
Intake Camshaft Adjuster tight/stuck
Intake Camshaft Adjuster faulty
Possible Solutions
Check Intake Camshaft Adjuster
When the Intake Camshaft Adjuster uses oil pressure to control the adjuster, check the oil pressure. The 1.8T is notorious for issues but any engine with low oil pressure or restrictions in the system could result in various timing DTC's such as 17748/P1340/004928.
Use Output Test, Meas. Value Blocks (MVB) & Basic Setting