Engine Controls - Fault Code 227/228, Mixture Deviation
Group 12Engine Electrical Systems
Bulletin Number
12 12 97
Woodcliff Lake, NJ
October 1997
Product Engineering
SUBJECT:
Fault Code 227/228
MODEL:
E36 - 328i with M52 engine
E39 - 528i with M52 engine
Situation:
"Check Engine" lamp is illuminated and the following faults are set in the Engine Control Module (DME):
FC 227 - Mixture deviation, cylinder 1-3 and/or
FC 228 - Mixture deviation, cylinder 4-6
Correction:
1. Check if the correct Air Mass Meter P/N 13 62 1 703 275 is installed. If the wrong Air Mass Meter is installed it will need to be replaced along with the Suction Silencer.
NOTE:
The rubber boot may not need to be replaced as it contains a rubber "downsizing" ring used for installing the smaller Air Mass Meter on other models. Remove the inner rubber ring from the rubber boot in order to install the larger Air Mass Meter.
As an example: If parts from a smaller engine (2.01) are installed in a 2.81, not enough air will be brought into the engine under certain driving conditions. A reduction in air flow can be noticed by checking the adaptation values, which in this case may reflect a "Multiplicative mixture adaptation" of approximately -6% to -8%.
2. If the correct air mass meter is installed check the adaptation values located in the DME diagnostic status section. The adaptation values can provide further insight as to what may have caused the fault to set. Once a certain adaptation threshold value is exceeded the system can no longer make the necessary correction and a fault is logged, as explained below.
Note:
After repair(s) are made pertaining to an adaptation related fault the adaptation values should be cleared. The vehicle can then be driven under various load conditions and readapted. By rechecking the adaptation values an indication as to the success of the repair can be obtained.
Parts Information:
Part Number Qty Description
13 62 1 703 275 1 Air Mass Meter
13 71 1 740 140 1 Suction Silencer (328i)
13 71 1 740 067 1 Suction Silencer (528i)
Warranty Information:
Parts and labor will be reimbursable under the terms of the applicable BMW Emissions or Limited New Vehicle Warranty.
Defect Code: 13 72 01 32 00
Removing and installing or replacing Air Mass Meter
Labor Operation: 13 62 560
Labor Allowance: 1 FRU
Replacing complete Air Cleaner
Labor Operation: 13 71 001
Labor Allowance: 4 FRU