Cylinder 1 Knock Control Limit Attained
2018-2018 Audi A6 3.0L Supercharged V6
The 2018 Audi A6 is equipped with a 3.0L V6 engine. Below you'll find detailed p1325 diagnostic code information including labor time estimates, cost ranges, and technician notes specific to this engine configuration.
Description
The ECU detected that the knock control system has retarded ignition timing on Cylinder 1 to its maximum limit. Persistent knock requires excessive timing retard that exceeds the system capability.
Symptoms
- Check Engine Light
- Loss of power
- Engine pinging or knocking audible
- Reduced fuel economy
Common Causes
- Low-octane fuel
- Carbon buildup on piston or valves
- Faulty knock sensor
- Overheating condition
- Incorrect ignition timing
Diagnostic Steps
- Switch to higher-octane fuel and clear codes
- Check for engine overheating
- Test knock sensor signal
- Inspect for carbon buildup
- Check ignition timing base setting
Repair Notes
Use the correct octane fuel; perform carbon cleaning if buildup is present.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0011Intake Camshaft Position Timing Over-Advanced Bank 1
- P0012Intake Camshaft Position Timing Over-Retarded Bank 1
- P0013Exhaust Camshaft Position Actuator Circuit/Open Bank 1
- P0014Exhaust Camshaft Position Timing Over-Advanced Bank 1
- P0015Exhaust Camshaft Position Timing Over-Retarded Bank 1
P1325 on Other Vehicles
Common Questions
What does code P1325 mean on a 2018-2018 Audi A6?
P1325 stands for "Cylinder 1 Knock Control Limit Attained". The ECU detected that the knock control system has retarded ignition timing on Cylinder 1 to its maximum limit. Persistent knock requires excessive timing retard that exceeds the system capability.
What are the symptoms of P1325 on a Audi A6?
Common symptoms of P1325 include: Check Engine Light, Loss of power, Engine pinging or knocking audible, Reduced fuel economy.
What causes P1325 on a 2018-2018 Audi A6?
Common causes of P1325 include: Low-octane fuel, Carbon buildup on piston or valves, Faulty knock sensor, Overheating condition, Incorrect ignition timing.
Last updated: March 2026