shogun
04-11-2013, 07:56 AM
E32, E31 M70, Date 01/1997
Rough or hunting idling and/or clutch judder when driving. "Check engine" lamp comes on in US vehicles.
Cause:
An increasing amount of water collects in the exhaust system due to unfavourable driving conditions such as frequent stop-and-go driving, long periods of idling and a lot of short-distance driving. This water builds up through e.g.:
-
separation of the water content in the fuel during cold start
-
as a product of the combustion process
-
through condensing of the air moisture in the exhaust as the exhaust system cools
down.
The ceramic sensor body that is heated immediately after the engine is started and quickly
achieves a high temperature is damaged by this cold condensate (thermoshock).
The following fault codes may be stored in the DME fault memory:
DME M1.2:
"10" - Oxygen-sensor control and/or
"28" - Oxygen sensor
DME M1.7:
"70" - Oxygen sensor and/or
"201" - Oxygen-sensor control
Affected
vehicles:
E31, E32 with M70
Manufacturing period: from start of series production up to October 1994.
Remedy:
If the oxygen sensor malfunctions repeatedly, not only the oxygen sensors must be replaced, but a Service solution must be retrofitted that has the following effect: delay of oxygen-sensor heating after the engine is started, depending on the engine temperature
and the engine load.
Procedure:
1.
Replace the oxygen sensors and clear the DME fault memory.
2.
Retrofit the Service solution consisting of an "oxygen-sensor-heater relay" and Service wiring harness.
-
Enclosure 1 contains a description of how to install the Service solution in E32 M70 vehicles with oxygen-sensor-heater relay (LSH) (manufacturing period:
11/86 up to 01/91 and 03/92 up to 03/94).
-
Enclosure 2 contains a description of how to install the Service solution in E32 M70 vehicles without oxygen-sensor-heater relay (manufacturing period: 02/91 up to 02/92).
-
Enclosure 3 contains a description of how to install the Service solution in E31 M70 vehicles with oxygen-sensor-heater relay (manufacturing period: 07/89 up to 01/91 and 03/92 up to 10/94).
-
Enclosure 4 contains a description of how to install the Service solution in E31 M70 vehicles without oxygen-sensor-heater relay (manufacturing period: 02/91 up to 02/92).
Found here
BMW Workshop Manuals - 8 Series E31 850Ci (M70) COUPE Workshop Manual - 4 SI Oxygen Sensor - Thermoshock E31 E32 M70 (http://bmw.workshop-manuals.com/8_Series_E31/850Ci_M70_COUPE/index.php?id=44)
Rough or hunting idling and/or clutch judder when driving. "Check engine" lamp comes on in US vehicles.
Cause:
An increasing amount of water collects in the exhaust system due to unfavourable driving conditions such as frequent stop-and-go driving, long periods of idling and a lot of short-distance driving. This water builds up through e.g.:
-
separation of the water content in the fuel during cold start
-
as a product of the combustion process
-
through condensing of the air moisture in the exhaust as the exhaust system cools
down.
The ceramic sensor body that is heated immediately after the engine is started and quickly
achieves a high temperature is damaged by this cold condensate (thermoshock).
The following fault codes may be stored in the DME fault memory:
DME M1.2:
"10" - Oxygen-sensor control and/or
"28" - Oxygen sensor
DME M1.7:
"70" - Oxygen sensor and/or
"201" - Oxygen-sensor control
Affected
vehicles:
E31, E32 with M70
Manufacturing period: from start of series production up to October 1994.
Remedy:
If the oxygen sensor malfunctions repeatedly, not only the oxygen sensors must be replaced, but a Service solution must be retrofitted that has the following effect: delay of oxygen-sensor heating after the engine is started, depending on the engine temperature
and the engine load.
Procedure:
1.
Replace the oxygen sensors and clear the DME fault memory.
2.
Retrofit the Service solution consisting of an "oxygen-sensor-heater relay" and Service wiring harness.
-
Enclosure 1 contains a description of how to install the Service solution in E32 M70 vehicles with oxygen-sensor-heater relay (LSH) (manufacturing period:
11/86 up to 01/91 and 03/92 up to 03/94).
-
Enclosure 2 contains a description of how to install the Service solution in E32 M70 vehicles without oxygen-sensor-heater relay (manufacturing period: 02/91 up to 02/92).
-
Enclosure 3 contains a description of how to install the Service solution in E31 M70 vehicles with oxygen-sensor-heater relay (manufacturing period: 07/89 up to 01/91 and 03/92 up to 10/94).
-
Enclosure 4 contains a description of how to install the Service solution in E31 M70 vehicles without oxygen-sensor-heater relay (manufacturing period: 02/91 up to 02/92).
Found here
BMW Workshop Manuals - 8 Series E31 850Ci (M70) COUPE Workshop Manual - 4 SI Oxygen Sensor - Thermoshock E31 E32 M70 (http://bmw.workshop-manuals.com/8_Series_E31/850Ci_M70_COUPE/index.php?id=44)