1999 AUDI A4 oil pressure

17-1


Lubrication system
components, removing and
installing Special tools

The following special tools and test equipment are
required for these operations
VAG 1342
Oil pressure tester
VAG 1527
Voltage tester
Pa
ge 1 of 15 Lubrication s
ystem com
ponents, removin
g and installin
g
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE01.17.1

17-3


6 -
Oil pan, lower
7 -
10 Nm (7 Nm)
8 -
Oil drain plug
40 Nm (30 ft lb)
9 -
Cover With integrated 5 bar (72 psi) and 11 bar
(159 psi) pressure relief valves
10 -
Oil cooler
11 -
Oil filter NOT interchangeable with older versionRevised lubrication system requires
different filter: Part no. 078 115 561 D
Pa
ge 3 of 15 Lubrication s
ystem com
ponents, removin
g and installin
g
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE01.17.1

17-6


Revised oil circulation system

Note:

Modifications compared to previous 2.8 liter V6
(Audi 90, Audi 100).
Only the modified components should be
installed on this engine.
1 -
Oil filter
Larger outer dimensions
2 -
Oil cooler Larger cross-sectional flow area
3 -
Cover for oil pan New
4 -
Pressure relief valve New
5 -
Oil supply to engine
6 -
Oil pump New
Pa
ge 7 of 15 Lubrication s
ystem com
ponents, removin
g and installin
g
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE01.17.1

17-7


7 -
Pressure relief valve 11 bar
New
8 -
Oil pick-up New
9 -
Oil pressure switch 1.8 bar Color: BrownChecking page 17
-9
Dynamic oil pressure warning system
function page 17
-11

Pa
ge 8 of 15 Lubrication s
ystem com
ponents, removin
g and installin
g
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE01.17.1

17-8


Function of revised oil circulation
Intake side
Oil is taken in from the oil pump -6- via the oil pick-
up pipe -8-.
Pressure side
Oil pressure comes from the oil pump -6- through
the upper part of the oil pan past the pressure relief
valve -7-, oil pressure switch -9-, oil cooler -2- and
oil filter -1- to the pressure relief valve -4-.
Pressure relief valve -4- controls the oil pressure to
the engine.
The pressure relief valve -7- is a safety valve that
opens only at high RPM and cold engine
temperature.
Advantages
Oil pressure is controlled from the oil filter and oil
cooler, so that the oil pressure available at those
locations is supplied via the pressure relief valve -4-
or from the oil pump.
Pa
ge 9 of 15 Lubrication s
ystem com
ponents, removin
g and installin
g
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE01.17.1

17-9

Oil pressure and oil pressure switch,
checking

Operational test and servicing the visible and
audible oil pressure indicator:

Electrical Wiring Diagrams, Troubleshooting
Component Locations binder.

Test requirements

Oil level OK
Oil pressure warning light -K3- comes on
with ignition on
Auto-Check system indication OK, if
applicable.
Engine oil temperature approx. 80 C (176
F) and radiator coolant fan must have
switched on at least once

Checking oil pressure switch

- Disconnect harness connector from oil pressure
switch.
Pa
ge 10 of 15 Lubrication s
ystem com
ponents, removin
g and installin
g
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE01.17.1

- Remove oil pressure switch and install into oil pressure tester VAG
1342.
- Connect cable -2- (brown) to Ground (GND).
- Connect cable -1- (blue) to oil pressure switch.
- Connect VAG 1527B voltage tester to cable -1- and battery positive
voltage (B+).
Pa
ge 11 of 15 Lubrication s
ystem com
ponents, removin
g and installin
g
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE01.17.1

17-10

- Start engine and slowly increase engine speed
(RPM).

At 1.6-2.0 bar (23-29 psi) pressure, the LED
must come on
If not:

- Replace 1.8 bar oil switch.
Pa
ge 12 of 15 Lubrication s
ystem com
ponents, removin
g and installin
g
11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE01.17.1