Electrical - Check Engine, Temp Gauge, Long Crank, Idle
Group 12Engine - Electrical
Bulletin Number
12 05 89 (1862)
Woodcliff Lake, NJ
June 1989
Technical Dept.
SUBJECT:
Moisture in C191 Multiplug
MODELS:
E30/E34 equipped with M20 motor (from 9/87 production)
Situation:
As a result of improper high pressure engine washing, moisture may enter the engine harness and migrate downward collecting in the C191 connector.
C191 multiplug is located low on the left side of the engine the starter motor) moisture contamination of this type can be overlooked.
Engine related complaints such as erratic temperature gauge operation, long cranking times, unsteady idle speed, etc. may occur as a result of moisture in the C191 multiplug.
In addition, illumination of the CHECK ENGINE light will indicate the likely area of the problem or which specific pin is affected.
Corrective Measures:
The remedy for this situation is broken down into the following three sections:
1. E30/M20 produced prior to 5/88, approximately (equipped with the former "cable in sheath" injection harness).
- Replace the existing injection harness with the improved version, P/N 12 51 1 724 521.
- Examine the condition of the electrical pins of the engine harness half of the C191 multiplug; then proceed to Step # 3.
- Inspect the engine harness segment of the C191 multiplug. If the electrical pins are free of moisture corrosion, carefully perforate the harness sheath at its lowest point to provide a Condensate drain point.
2. E30, E34/M20 produced from 5/88, approximately (equipped with the new "cable rail" injection harness).
- Remove cable rail injection harness. Blow dry with moderate compressed air.
- Examine the electrical pins in the cable rail half of the C191 multiplug. If corrosion is present, replace the cable rail unit, P/N 12 51 1 719 606.
- Check that the cable rubber grommets are properly seated (arrow).
- Apply silicone paste where the C191 down cable passes thru the C191 weather boot.
- Verify that the four phillips head screws which retain the cable rail lid are tight.
- Reinstall the cable rail injection harness.
- Inspect the engine harness segment of the C191 multiplug. If the electrical pins are bee of moisture corrosion, carefully perforate the harness sheath at its lowest point to provide a condensate drain point.
3. All vehicles after injection harness repair/replacement
- Should the engine harness segment of the C191 multiplug show corrosion, the multiplug housing should be cleaned and the female connectors replaced.
- Renewal of the C191 female connectors should be performed using the guidelines and tool listed in S.I. 12 01 88 (1574). Use the pin location information which follows for correct wire installation.
- After renewing the C191 connectors, carefully perforate the harness at it's lowest point to provide a condensate drain point.
Special Note:
The weather sealing measures covered in this S.I. Bulletin will provide superior moisture protection for all normal operating conditions.
However, as S.I. 12 03 89 (1838) directs, high pressure steam type cleaning is not an approved practice for BMW engines. Such high pressure cleaning will tax the sealing integrity of any electrical harness and has been found to create problems which otherwise would not have occurred.
Please have all workshop personnel read and follow the points listed in S.I. 12 03 89 (1838).
Warranty Information:
Parts and Labor reimburseable under the terms and provisions of the BMW 3 Year/36,000 Mile New Car Limited Warranty
Defect code: 61 11 08 75 00
Corrective measure Labor operation Labor allowance
E30 E34
# 1 (up to 5/88 production) 00 50 184 7 6
# 2 (to 5/88 production) 00 50 185 8 7
# 3 (when required) 00 50 797 8 8