(VIN: -039999) Trionic T7 V6 OBD II (B308E)

P1393
Cylinder 3 Misfire Detected. Catalyst Damaging. Fuel Level Low.

Fault symptoms
- CHECK ENGINE.
- Running unevenly and misfiring.

On-Board Diagnostics
Type of diagnosis:
- Continuous. But interrupted when fault criteria fulfilled and does not restart until next driving cycle.

Enable conditions:
- General conditions for this trouble code: Atmospheric pressure must exceed 78 kPa and the engine coolant and intake air temperatures must exceed 7°C.
- Engine started. Fuel level below 4 litres. Main relay voltage exceeding 10V. Ignition discharge module combustion signals registered. The number of missing combustion signals is accumulated for each cylinder during 200 engine revolutions. The total number of accepted misfires during 200 engine revolutions is specified in a load and engine speed-dependent matrix.

Fault criteria:
- Number of missing combustions exceeding number of accepted misfires.

Dependents:
- P1313 and P1324.

System reaction to a fault:
- Under high engine loads, closed loop will be blocked while misfiring occurs.

OK report:
- Provided that fault criteria have not been fulfilled during the driving cycle, an OK report will be given when the ignition is turned oft and before the engine has stopped. Two types of OK report can be given: Type 1: If a diagnostic trouble code is already stored for the diagnosis and the same operating conditions have arisen (engine coolant temperature over or under 71°C, engine speed 375 rpm and load 10%). Type 2: If there are no diagnostic trouble codes stored for the diagnosis or the same operating condition have not arisen.

Fault handling: See "Fault diagnosis, general" for more information.
- Type I.

Diagnostic help
If any other trouble codes have been generated, check whether fault diagnosis should start with them. Drive the car in the load and engine speed range shown by Freeze Frame. If the engine does not misfire, the trouble code was probably due to the fuel level being too low. Drive the car so that the catalyst diagnosis is performed. If necessary, change the catalytic converter.

If the engine misfires during test driving, conduct a general inspection of connectors and hoses, and then a thorough check of compression, ignition and fuel system.

Functions in the diagnostic tool related to the fault:
- Diagnostic status for the diagnosis.
- Misfire counter for the relevant cylinder.
- Activating misfire counter reset.
- Activating ignition trigger for relevant cylinder.
- Activating injector test for relevant cylinder.

See also the description of activations under "Fault diagnosis, general" for more information.

Checking the wiring
Jiggle the wiring harness at several points and in different directions to detect intermittent breaks and short circuits. Observe the multimeter, diagnostic tool or test lamp during the check.