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Engine Runs Rich: Check ECM & O2S Ground Connections (GROUP 24, NO. 93-10)

Publication date: 1993-12-15
Reference number: GROUP 24, NO. 93-10

ENGINE RUNS RICH: CHECK ECM & O2S GROUND CONNECTIONS

ENGINE RUNS RICH: CHECK ECM & O2S GROUND CONNECTIONS

TECHNICAL SERVICE BULLETIN

Reference Number(s): GROUP 24, NO. 93-10, Date of Issue:  December 15, 1993

RICH ENGINE RUNNING CONDITION

Model(s): 1990-93 Volkswagon Cabriolet With Digifant MFI

Group: 24 - Multiport Fuel Injection

Bulletin No.: 93-10

Date: December 15, 1993

CONDITION

A rich engine running condition may be caused by an improper or loose Engine Control Module (ECM) and Oxygen Sensor (O2S) Ground (GND) connection.

SERVICE

- Check the Ground (GND) connection on the engine at the coolant flange mounting stud. See Fig 1 -arrow-.

- Ensure that the coolant flange mounting stud is installed tightly in the Cylinder Head and tighten if necessary.

- Ensure that the Ground (GND) Connection on the stud is clean and tight. Clean and tighten the Connection as necessary.

Fig 1: Ground Connection On Mounting Stud
G94E51635