T8 / P0172 00
Read the instructions below then
start the fault diagnostic procedure.
Symptom: Fault indicator lamp (for further information see WIS Fault diagnosis, general)
The engine may stop after starting, run unevenly and misfire.
Long Term Fuel Trim Multiplicative. Min Value, Air/Fuel too Rich.
Fault symptom
Fault indicator lamp (for further information see WIS Fault diagnosis, general)
The engine may stop after starting, run unevenly and misfire.
On-board diagnosis
Type of diagnosis:
Enable criteria:
| The engine has started and lambda control is active. |
| A multiplicative adaptation is carried out. |
| NONE of the following DTCs must be detected: |
Fault criteria:
| Multiplicative adaptation has bottomed at -25%. |
Dependent:
System reaction to a fault:
OK report:
| Provided that the fault criteria are not fulfilled during the operating cycle, there is an OK report upon ignition shut-off before the engine stops. Two types of OK reports are possible: Type 1: If there is already a DTC stored for the diagnosis and operating conditions were the same (coolant temperature over or under 71°C, engine speed 375 rpm and load 10%). Type 2: If there is no DTC stored for the diagnosis or if operating conditions were not the same. |
Fault handling:
| (See section Fault handling II, "Emission-related misfiring or fault in fuel system" for more information.) |
Diagnostic help
Diagnosis regards:
| Checking air/fuel ratio. With this DTC, the engine will be getting too little air (leak) or too much fuel. |
Functions in the diagnostic tool related to the fault:
| • | Multiplicative Adaptation |
| • | Airmass Deviation from Calculated |
| (See also description of readings/activations in diagnostic tool) |
