coolant AUDI A4 1999 B5 / 1.G APB Engine Motronic Multiport Fuel Injection System Servising Workshop Manual

24-7


1 -
Harness connector forOxygen Sensor
(O2S) Behind Three Way Catalytic
Converter (TWC) -G130 and Heater for
Lambda-probe 1 -Z29
4-pin green
2 -
Harness connector forOxygen Sensor
(O2S) 2 Behind Three Way Catalytic
Converter (TWC) -G131 and Heater for
Lambda-probe 2 -Z30 4-pin brown
3 -
Harness connector for Heated Oxygen
Sensor (HO2S) and Oxygen Sensor (O2S)
Heater 4-pin black
4 -
3-pin harness connector For Knock sensor (KS) 1 -G61
5 -
Engine Coolant Temperature (ECT)
Sensor -G62 On cooling pipe behind cylinder bank 1
6 -
Wastegate Bypass Regulator Valve -N75
7 -
EVAP Canister Purge Regulator Valve -
N80
Pa
ge 9 of 90 Motronic Multi
port Fuel In
jection
(MFI
) system, servicin
g
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.24.1

24-27

Idle speed, checking


Test conditions

No leaks in exhaust system
Coolant temperature at least 80 C

Electrical consumers switched off (radiator
fan must not run during the check)
A/C switched off
Pressure gauge not connected
Selector lever in position P or N (vehicles
with automatic transmission)

Checking idle speed

Notes:
The idle speed cannot be adjusted.
The idle speed is tested during the basic setting
of the engine.
Pa
ge 31 of 90 Motronic Multi
port Fuel In
jection
(MFI
) system, servicin
g
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.24.1

24-59

Mass Air FLow (MAF) sensor -G70,
checking


Requirements

Coolant temperature at least 80 C (175 F)

Electrical consumers switched off (radiator
fan must not run during test)
A/C switched off
Fuse for mass air flow sensor OK

Electrical Wiring Diagrams, Troubleshooting &
Component Locations

Checking function

- Connect vehicle diagnostic, testing and
information system VAS5051 or VAG1551 scan
tool and select engine electronics control
module by entering address word "01" Page
01
-9 . When doing this the engine must be at
idle.
Pa
ge 69 of 90 Motronic Multi
port Fuel In
jection
(MFI
) system, servicin
g
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.24.1