Additive Adaptive Mixture Correction TRA Bank 1 Drive Cycle B

DTC P0172
Additive adaptive mixture correction TRA bank 1 Drive cycle B:Signal out of range - below minimum.

Possible causes by suggested order of priority:
^ Air leak between MAFS and inlet manifold (high TRA).
^ Air leak in inlet manifold (high TRA).
^ MAF sensor inaccurate.
^ Fuel leak in one injector (low TRA).
^ Part load breather pipe.

Air Leak Between MAFS and Inlet Manifold (high TRA).
CHECK THE FOLLOWING:
^ Fuelling adaption TRA also abnormally high on bank B (right).
^ There are no misfire faults set on the vehicle.
^ There are no oxygen sensor or catalyst faults set on the vehicle.
POSSIBLE FAULTS
^ Air leak near to MAFS.
^ Air leak near to IACV.
^ Air leak near to throttle body.
DIAGNOSTIC HINTS
^ If TRA adaption is normal on bank B (right) the problem is not an air leak.
^ Misfire, oxygen sensor or catalyst faults could give a false indication of an air leak fault.

Air leak in inlet manifold (high TRA).
CHECK THE FOLLOWING:
^ Fuelling adaption TRA also abnormally high on bank B (right)
^ There are no misfire faults set on the vehicle.
^ There are no oxygen sensor or catalyst faults set on the vehicle.
POSSIBLE FAULTS
^ Air leak in inlet manifold gaskets or seals.
^ Porous inlet manifold casting (especially on new manifolds).
^ Air leak around injector or spark plug seals.
^ Air leak in injector or spark plug.
DIAGNOSTIC HINTS
^ If TRA adaption is normal on bank B (right) the problem is not an air leak.
^ Misfire, oxygen sensor or catalyst faults could give a false indication of an air leak fault.

MAF Sensor Inaccurate.
CHECK THE FOLLOWING:
^ Fuelling adaption TRA is also abnormal on bank B (right).
^ There are no misfire faults set on the vehicle.
^ There are no oxygen sensor or catalyst faults set.
POSSIBLE FAULTS
^ MAF sensor is functioning but inaccurate.
DIAGNOSTIC SUGGESTIONS
^ Renew MAFS or test by substitution with known good unit.

Fuel Leak In One Injector (low TRA).
CHECK THE FOLLOWING:
^ Fuelling adaption TRA is slightly reduced or normal on bank B (right) and reduced on bank A (left).
^ There are no misfire faults set on bank A (left) the vehicle.
^ There are no oxygen sensor or catalyst faults set on bank A (left).
POSSIBLE FAULTS
^ Continuous fuel seepage in one injector.
DIAGNOSTIC HINTS
^ Misfire, oxygen sensor or catalyst faults could give a false indication of a fuel leak fault.
^ Look for evidence of the fuel leak (excess fuel present in cylinder).
^ Fit a pressure gauge to the fuel rail and check that the fuel pressure does not die away quickly when the ignition is switched off (indicating a leak).

Part Load Breather Pipe.
CHECK THE FOLLOWING:
^ Part load breather pipe connections.
^ State of the part load breather pipe for cracks etc.