Audi Workshop Service and Repair Manuals > A4 Mk2 > Power unit | Simos direct petrol injection and ignition system (6-cyl. 3.2 ltr. 4-valve) | Mixture preparation system, electronic inj.,Gas | Servicing Simos injection system | Removing and installing Lambda probe after catalytic converter

Removing and installing Lambda probe after catalytic converter - bank 2 (left)

Special tools and workshop equipment required

t	Lambda probe open ring spanner set -3337-

Removing

Note

All cable ties which are released or cut open when removing must be refitted in the same position when installing.

–	Pull off engine cover (rear) -arrows-.

–	Unbolt coolant expansion tank -arrow-.

–	Unplug electrical connector for coolant shortage indicator switch -F66- at bottom of expansion tank and move coolant expansion tank to one side with coolant hoses -1- and -2- attached.

–	Unplug electrical connector -1- for Lambda probe 2 after catalytic converter -G131- and move wiring clear (downwards).

Note

Disregard -item 2-.

–	Unscrew Lambda probe -2- using Lambda probe open ring spanner set -3337-.

Note

Shown in illustration with engine removed.

Installing

Installation is carried out in the reverse order; note the following:

Note

t	Renew O-ring.

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	If reinstalling the old Lambda probes, coat the threads with high-temperature paste → Parts catalogue. The paste must not get into the slots on the probe body.

t	Fit all cable ties in the original positions when installing.

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.

Tightening torque

Component	Nm
Lambda probe in front exhaust pipe	55

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