Audi Workshop Service and Repair Manuals > A3 Mk2 > Power unit | Direct petrol injection and ignition system (4-cyl. 2.0 ltr. 4-valve) | Mixture preparation system, electronic inj.,Gas | Injection system | Removing and installing Lambda probes (before catalytic converter)

Removing and installing Lambda probes (before catalytic converter)

The components Lambda probe 2 -G108- and Lambda probe 2 heater -Z28- are not fitted on engines with code letter BVZ.

Special tools and workshop equipment required

t	Lambda probe open ring spanner set -3337-

Fitting location of connectors for Lambda probes before catalytic converter

1 -	Connector for Lambda probe 2 -G108- and Lambda probe 2 heater -Z28- (for cylinders 2 and 3) “not fitted on engines with code letter BVZ”

2 -	Connector for Lambda probe -G39- and Lambda probe heater -Z19- (for cylinders 1 and 4)

–	Unplug connector for corresponding Lambda probe.

Fitting location of Lambda probes before catalytic converter

1 -	Lambda probe -G39- and Lambda probe heater -Z19- before catalytic converter “engines with code letters BLY and BVZ, see next illustration”

2 -	Lambda probe 2 -G108- and Lambda probe heater 2 -Z28- before catalytic converter “not fitted on engines with code letter BVZ”

Lambda probe -G39--2-“engine code letters BLY and BVZ”

Removing

–	Unplug electrical connector for Lambda probe -G39- and Lambda probe heater -Z19-.

–	Unscrew relevant Lambda probe using tool from Lambda probe open ring spanner set -3337-.

Installing

When installing, note the following:

Note

t	Threads of new Lambda probes are already coated with assembly paste; the paste must not get into the slots on the probe body.

t	In the case of a used Lambda probe grease only the thread with high-temperature paste. The paste must not get into the slots on the probe body. High-temperature paste → Parts catalogue

t	When installing, the Lambda probe wire must always be reattached at the same locations to prevent it from coming into contact with the exhaust pipe.

t	Tightening torque: 55 Nm.

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