1997 AUDI A8 AHA Engine Intake Manifold Tuning System Workshop Manual

24-161
If LED stays on continuously:

If wiring is OK: - Check wiring from terminal 2 of 2-pin connector to terminal 64 of test
box for ground per wiring diagram.
- Replace Motronic ECM -J220- page 01
-68
.
- Carry out adaptation of throttle valve control module to ECM page
24
-150
.
- Check readiness code page 01
-70
. If Diagnostic Trouble Code
(DTC) memory has been erased, or ECM was disconnected, generate
new readiness code page 01
-73
.
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24-162

Vacuum system, checking for leaks


- Let engine run 2 to 3 minutes at idle (for vacuum
to build up).

- Switch ignition off.

- Remove 2-pin connector from intake manifold
tuning valve -N156- (change-over valve).

- Connect jumper wire (from VAG1594) from one terminal of -N156- to
engine ground.
- Use VAG1248/3A remote, adapter wire VAG1348/3-2 and auxiliary
wire to connect second terminal of -N156- to B+.
- Activate intake manifold tuning valve -N156-, using remote control
VAG1348/3A, for approx. 2 to 3 min.
The vacuum solenoid must remain actuated during this time.
Pa
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) syste
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11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
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24-163
If vacuum solenoid releases, check solenoid as
follows:

- Remove vacuum line from vacuum solenoid for
intake manifold change-over.

- Connect VAG1390 hand pump to vacuum
solenoid.

- Activate VAG1390 hand pump and watch
change-over process.

- Check vacuum solenoid for leaks.

Vacuum solenoid should not return to initial
position as long as vacuum is being applied by
hand pump.
If vacuum solenoid returns:

- Replace vacuum solenoid.
Pa
ge 11 of 11 Intake Manifold Tunin
g (IMT
) syste
m
11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU03.24.3