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ECM - Engine Power Restricted

DATE: May 15, 1993

GROUP: 21

NUMBER: 93-02

SUBJECT:
Engine Power Restricted

MODEL(s):
S4 from 1992 m.y.
Engine Code AAN

Supersedes Tech. Bulletin 21-93-01 of 3/15/93

CONDITION

Engine power restricted

CAUSE

^ Moisture separator in vacuum line between intake manifold and Engine Control Module (ECM) leaking.

^ Vacuum line connection on intake manifold is partially blocked by Loctite contamination. As a result, the ECM does not recognize actual boost pressure.

^ Vacuum line between intake manifold and ECM is kinked in area of fire wall

PRODUCTION

Still being investigated.

SERVICE

- Check On-Board Diagnostics with scan tool VAG 1551. In most cases Diagnostic Trouble Code (DTC) 00519 (manifold vacuum sensor) is recorded.

- Check vacuum line for leaks.

- Check moisture separator, located in right side footwell near ECM. Pay particular attention to correct welding of moisture separator housing halves.

- If necessary, replace moisture separator1 Part No. 034 131527 A

- Check vacuum line connection at intake manifold and clean as necessary. The connection must not be blocked or restricted.

- Check vacuum line routing through firewall for kinks.