Page 131
220-6
Lubrication System
Fig. 12. Oil cooler mounting nut in engine compartment near radiator.
6. Unbolt the cooler together with its shroud from below.
Carefully pull the cooler and shroud down. See Fig. 13.
Unbolt the shroud 'from the cooler and remove the lines
from the cooler.
Installation is the reverse of removal.
Fig. 13. Oil cooler being removed from recess behind headlight.
Fig. 11. Oil cooler and related components for turbo engines.
OIL COOLER (TURBO MODELS ONL Y)
Page 132
---Fuel Pump and Fuel Tank
234-1
234 Fuel Pump and Fuel Tank
General
Roller-type Fuel Pump Assembly
with Supply Pump
Rotor-type Fuel Pump Assembly
Safety Precautions
Fuel Pump Troubleshooting
Basic Troubleshooting Principles
Fuel Pump Noise
Operating Fuel Pump for Tests
Supply Pump Quick Check
(roller-type pump only)
To test roller-type supply pump
Fuel Pump
Fuel Pump Delivery Rate
To test pump delivery
Fuel Pump Electrical Tests
Testing Fuel Pump Circuit
To test fuel pump relay control circuit
Checking for Voltage at the Fuel Pump
Testing Turbo Over-pressure Switch
(1985-1988 models only)
234-1
234-2
234-2
234-2
234-3
234-3
234-4
234-4
234-5
234-5
234-5
234-5
234-5
234-6
234-6
234-7
234-7
To test turbo over-pressure switch
Replacing Roller-type Pump
To replace roller-type pump assembly
Replacing Rotor-type Pump
To replace rotor-type pump assembly
To replace fuel pump screen
(models with rotor-type pump only)
Replacing Fuel Pump Check Valve
Fuel Tank and Lines
Fuel Tank
To remove and install fuel tank
To remove and install
fuel gauge sender unit
To replace fuel tank rollover valve
Fuel Lines
To replace fuel lines inside car
To replace banjo fitting on fuel line
234-8
234-8
234-8
234-11
234-11
234-13))('::
234-13!I~i
234-14: N
234-14
234-14
234-15
234-15
234-16
234-16
234-16
TABLES
a. Fuel Pump Applications
234-2
234-8
GENERAL
The injection-molded plastic fuel tank is located beneath
the car, behind the rear seat. The fuel gauge sender and the
electric fuel pump are mounted in the top of the tank. See Fig.
1. The fuel tank is designed to prevent overfilling and allow for
fuel expansion. The filler cap contains a valve to prevent a
vacuum from occurring in the tank. To prevent a backflow of
fuel from the tank when the car is stopped, there is a check
valve in the fuel return line from the fuel injection system.
The fuel pump is an electric rotary pump mounted inside the
fuel tank. The fuel pump constantly circulates fuel throughout
the system. Fuel is drawn from the tank, filtered, routed to the
fuel injectors, regulated to maintain a constant pressure, and
then recirculated back into the fuel tank.
Fuel tank
filler neck
Fuel gauge
sender
",
NOTE
Fuel filter replacement is covered in 1 LUBRICATION AND
MAINTENANCE.
87406
Fig. 1. Fuel tank and related components.
Fuel flows through the pump and over the pump's electric
motor. This helps cool the pump during normal operation. An
inlet strainer helps prevent pump clogging. The main pump is
GENERAL
:
Page 133
234-2
Fuel Pump and Fuel Tank
mounted in a reservoirto help prevent fuel starvation. The fuel
pump contains a bypass valve to prevent high pressure from
damaging the system if there is a kinked or blocked fuel line.
Also, there is a check valve at the pump outlet to hold pressure in the system after the pump is turned off.
The electrical current that operates the fuel pump is controlled by a relay. This ensures that the pump will not flood the
engine, or continue running in the event of an accident or if the
engine stalls. Turbo models have an additional pump safety
feature that turns the pump off during overboost situations.
Two different fuel pump combinations and mountings are
installed on Saab 900 models depending on the model year.
See Table a. The two pump types are not interchangeable,
owing to a different fuel tank design.
Table a. Fuel Pump Applications
Model
Pump type
1986-1988 Non-turbo *
Roller
1985-1989 Turbo models*
1989- and later Non-turbo
Rotor
1990 and later, Turbo
'Some early models may be equipped with a special replacement rotor-type fuel
pump. This dealer-installed service pump was designed to eliminate a complaint of
poor driveability or noisy pump operation and can be identified by its rubber mounting
collar-other rotor-type pumps are mounted with a threaded plastic collar.
Roller-type Fuel Pump Assembly
with Supply Pump
Fig. 2 shows the roller-type fuel pump assembly. The pump
is mounted in a fuel reservoir that is fed with fuel by the electric
supply pump. In addition, the fuel return from the fuel injection
system also feeds the fuel reservoir. This design helps prevent fuel starvation during hard cornering. The reservoir has a
safety valve that opens at 0.1 bar (1.4 psi). The pump is
mounted to the tank by a rubber collar.
NOTE
It may require at least two gallons of fuel to prime the pump if
the car ran out of gas. If the car is not on level ground, additional fuel may need to be added.
Rotor-type Fuel Pump Assembly
Fig. 3 shows the rotor-type "ejector-style" fuel pump. The
rotor-type pump is similar to the roller-type pump, although
the separate supply pump is not used. The ejector picks up
additional fuel from the bottom of the tank and forces it into the
reservoir.
GENERAL
87277-82/959
1. Fuel pump
2. Reservoir (pressure vessel)
3. Supply pump
4. Pump outlet check valve
~----------
Fig. 2. Roller-type fuel pump assembly.
Safety Precautions
Please read the following warnings before doing any work
the fuel pump, fuel tank or fuel lines.
WARNING
• Always disconnect the negative (-) battery terminal and cover the terminal with an insulated material whenever working
on any fuel related component.
• Gasoline is dangerous to your health. Wear hand and skin
protection when working on the fuel system. Do not breathe
fuel vapors and always work in a well-ventilated area.
• Fuel and fuel vapors will be present during many of the operations described in this repair group. Do not smoke or create
sparks. Have an approved fire extinguisher handy.
• The fuel injection system is designed to maintain pressure
in the system after the engine is tumed off. Fuel will be expelled under pressure as fuel lines are disconnected. This can
be a fire hazard, especially if the engine is warm. Always wrap
a clean shop rag around the fitting before loosening ordisconnecting any fuel line.
Page 134
Fuel Pump and Fuel Tank
234-3
CAUTION
• Avoid the use of compressed air nearby, and do not move
the car while the fuel system is open.
9
1----6
• When replacing parts, install only new, clean components.
Seals and a-rings should always be replaced rather than reused.
NOTE
To help prevent poor fuel delivery due to pump cavitation,
Saab recommends avoiding the use of alcohol-enhanced fuel
above ambient temperatures of 75°F (24°C).
+-+--v----1
Basic Troubleshooting Principles
87279-8211432
1.
2.
3.
4.
5.
Main fuel pump
Ejector pump
Filter
Reservoir
Fuel delivery line
Fig. 3.
6.
7.
8.
9.
10.
Fuel return line
Threaded retaining collar
Seal
Spring
Filter breather pipe
Rotor-type fuel pump assembly.
FUEL PUMP TROUBLESHOOTING
The fuel supply system is an integral part of the operation of
the fuel injection system. Problems such as a no-start condition, hesitation or stalling may be due to poor fuel delivery.
There are some preliminary tests to quickly determine if the
fuel pump or its electrical circuit are causing the problem.
Some of the tests described below require special test equipment, such as a fuel pressure gauge.
The basic function of the fuel pump is to deliver an adequate
amount pressurized fuel. Problems caused by a fault with fuel
pump range from a no-start condition to intermittent poor performance and driveability. These problems can be the result
of a fault in the pump electrical circuit or a worn or faulty pump.
Begin troubleshooting with a simple check of the fuel pump
electrical circuit. The pump should run while cranking the engine with the starter. If necessary, remove the access cover
under the trunk floor and listen or feel to see whether the
pump is running. If the pump does not run, see Fuel Pump
Electrical Tests below.
If fuel delivery problems are suspected, begin troubleshooting with a check of the fuel pump delivery rate. See Fuel
Pump Delivery Rate. The test will indicate whether further
tests are necessary. This is especially important on high-mileage cars, where normal pump wear may decrease delivery
volume.
Also check for correct pump installation, a clogged pump
strainer, or a bad supply/ejector pump. Any combination of
these may cause the problems listed above.
NOTE
General engine management and driveability troubleshooting
should begin by consulting 200 Engine-General.
NOTE
• On Turbo models, a faulty over-pressure switch may cause
momentary fuel pump cut-out or a no-start condition. See
Testing Turbo Over-pressure Switch (1985-1988 models
only) for more information.
Cleanliness is essential when working with the fuel system. Even a tiny particle of dirt can cause trouble if it reaches
an injector.
CAUTION
• Thoroughly clean fuel line unions before loosening or disconnecting them. Use only clean tools.
• Keep removed components clean, and seal or cover them
with a clean, lint-free cloth, especially if the repair cannot be
finished immediately.
• On models with rotor-type pumps, poor performance may be
caused by a ruptured or ballooned delivery hose in the pump
assembly. This hose is available as a replacement part. See
Replacing Rotor-type Pump for additional information.
• Poor driveability or performance on 1988 and some 1989
models with roller-type or rotor-type pumps may be due to a
blocked return line check valve at the fuel tank, causing excessive line pressure. The problem is covered under Saab's
vehicle warranty. For more information see an authorized
Saab dealer.
FUEL PUMP TROUBLESHOOTING
Page 135
234-4
Fuel Pump and Fuel Tank
NOTE
During 1990 model production, a modified rotor-type pump
was installed as a running change. The new design helps
eliminate pump cavitation, pump noise, and pump overheating. The new pump can be retrofitted to earlier models with the
rotor-type (threaded collar) pump.
Fuel Pump Noise
Fuel pump noise does not always indicate a bad pump. The
amount of noise that is transmitted to the passenger compartment varies with the car. Humming or buzzing at various levels is generally considered normal, while clicking, ratcheting
or grinding may signal imminent pump failure.
On roller-type pumps, improper pump or fuel tank installation can increase pump noise, as can a faulty supply pump.
On rotor-type pumps, a clogged ejector pump can often cause
noise. Many times the main fuel pump is replaced needlessly
when the supply or ejector pump is at fault.
NOTE
Supply pump test procedures are covered below under Supply Pump Quick Check (roller-type pump only).
Fig. 4. Jumper wire with flat-blade connectors and switch for running fuel pump without running engine.
To run the pump, remove fuses number 27 and 30. With the
ignition off, connect the jumper wire and switch as shown in
Fig. 5. Turn the switch ON to run the pump.
Operating Fuel Pump for Tests
The electric fuel pump only runs when the cars is running or
being started. This is to prevent running the fuel pump indefinitely if the engine stalls. Testing the fuel pump and the fuel injection system requires running the pump with the engine off.
The procedure for operating the pump uses a temporary
wiring connection on the fuse/relay panel to bypass the fuel
pump relay. The preferred method is to use a remote switch,
such as the Saab special tool, Part No. 83 93886, but you can
accomplish the same thing with a homemade jumper wire and
an in-line switch. See Fig. 4.
87281
CAUTION
• A homemade jumper wire with a switch should be at least
1.5 mm metric wire size (14 gauge-AWG) and, for safety,
should include a 20 amp in-line fuse.
• Avoid damaging the fuse sockets. The ends of the jumper
wire should be flat-blade connectors that are the same size as
the sockets in the fuse panel.
• Connect and disconnect the remote switch or jumper wire
only with the switch in the off position.
FUEL PUMP TROUBLESHOOTING
Fig. 5. Schematic view of jumper wire and switch connected at fuse
sockets (fuses removed) for running fuel pump. Fuse/relay
panel is in engine compartment, on top of left fender.
NOTE
If the pump runs only when the jumper is connected, the relay
or wiring is faulty. If the pump doesn't run with the jumper installed, the problem is in the wiring to the pump or the pump
itself. See Fuel Pump Electrical Tests for more information
Page 136
Fuel Pump and Fuel Tank
Supply Pump Quick Check
(roller-type pump only)
The following test will help determine whether a faulty supply pump is the cause of fuel delivery problems. A faulty supply pump usually manifests itself through a noisy fuel pump.
234-5
NOTE
If fuel comes out of the relief valve, the supply pump is working correctly. If no fuel comes out, the supply pump is most
likely faulty and should be replaced. The supply pump is available as a replacement part. See Replacing Roller-type
Pump below.
WARNING
• The fuel tank must be no more than 3/4 full when making this
check or fuel may be spilled.
• Fuel will be expelled. Do not disconnect wires that could
cause sparks. Have a fire extinguisher handy. Perform the test
outside if possible. Have a supply of rags handy to clean up
any spills.
Relief valve
To test roller-type supply pump
1. Working in the trunk, remove the pump access cover.
Disconnect the main pump terminals and slacken and
remove the mounting boot clamp. See Fig. 6.
Fuel
reservoir
Supply pump
I
IL'"r----n~
-",-~,--,
87283
Fig. 7. Cutaway view of roller-type fuel pump shoWing fuel forced out
of relief valve as supply pump operates.
4. When finished, clean up all spilled fuel and reinstall the
pump mounting boot.
Fig. 6.
Fuel pump mounting boot clamp being loosened using flexible socket dnver.
2. Carefully peel back the pump mounting boot so that the
top of the fuel pump reservoir is visible.
3. Run the fuel pump as described above under Operating Fuel Pump for Tests As the supply pump runs, fuel
should be forced out of the reservoir relief valve. See
Fig. 7.
FUEL PUMP
Fuel Pump Delivery Rate
This test checks the fuel pump output. Insufficient fuel delivery can result in poor performance, hard starts, hesitation,
and stalling.
To test pump delivery
WARNING
The fuel forced out of the relief valve will be partially vaporized
and is extremely flammable. Do not smoke or create sparks.
Have an approved fire extinguisher handy.
1. Working in the engine compartment, disconnect the
fuel return line from the pressure regulator. See Fig. 8.
Attach a length of fuel line to the pressure regulator and
place the hose into a 2 liter (2 quart) container.
FUEL PUMP
Page 137
234-6
Fuel Pump and Fuel Tank
Fuel Pump Electrical Tests
WARNING
Fuel will be expelled as the line is disconnected.
1
I
The fuel pump electrical circuit is relay controlled, which
means that power to the pump must pass through the relay
before the pump can run. The LH control unit controls the relay.To keep the relay closed and the pump running, the LH
control unit must get a signal that the engine is turning over.
This pulse signal comes from the ignition system. 1985
through 1988 Turbo models use an additional over-pressure
switch to prevent engine damage as a result of turbocharger
wastegate malfunction. The over-pressure switch cuts off
power to the fuel pump relay whenever boost pressure is
above a safe level.
NOTE
• Testing of the turbo over-pressure switch is covered below.
87284-S2I306
Fig. 8.
Disconnect fuel return line at pressure regulator (arrow). Attach length of hose to regulator and place hose end into container.
2. Install the switched jumper (see Fig. 5) and run the fuel
pump for exactly 30 seconds. Check the amount of fuel
in the container.
• An additional engine over-rev protection feature tums off the
fuel injectors if the engine speed goes above 6,000 rpm. This
feature is handled by the LH control unit.
If the pump fails to run at all when the starter is cranked, the
problem can be due to one of the following: the fuel pump relay, the electrical circuit, the LH control unit, or the pump itself.
Always checkthe fuel pump fuse first. This is especially true
in cold weather when moisture in the fuel may freeze in the
pump, overloading the circuit and blowing the fuse.
• minimum of 900 rnl (30 oz.) in 30 seconds
CAUTION
• Do not bypass a failed fuse to power the circuit directly until
finding out why the fuse has failed.
Causes of insufficient delivery:
• Repeated fuse failures indicate an electrical problem, usually a short to ground or an overloaded circuit. A ci rcuit overload
can be caused by a faulty component, such as a jammed
pump.
Fuel Pump Delivery Volume
• system pressure incorrect. Check fuel pressure as
described in 240 Fuel Injection
• clogged pump strainer/fuel filter/supply line
• voltage at fuel pump incorrect. See Fuel Pump
Electrical Tests
• worn fuel pump
If fuel delivery volume is low, reconnect the fuel return line
to the pressure regulator. Install a pressure gauge as described in 240 Fuel Injection. Run the fuel pump and slowly
clamp shut the fuel return line at the pressure regulator. Immediately release the pinched hose as soon as the pressure
approaches 6 bar (83 psi). When the return line is clamped
shut, the gauge needle should rapidly rise to about 6 bar (83
psi). If not then the pump is probably faulty.
CAUTION
Allow the fuel pressure to rise slowly. Do not allow the pressu re to exceed 6 bar (83 psi). Damage to the fuel pump or
lines can result.
FUEL PUMP
NOTE
For the best troubleshooting results, perform all tests listed
below in the sequence in which they appear.
Testing Fuel Pump Circuit
Check the circuit that powers the pump by bypassing the relay to run the pump. Remove the fuel pump relay, shown in
Fig. 9. Install ajumper wire between sockets 30 and 8lb in the
relay panel. The pump should run.
If the pump runs with the relay bypassed, you can assume
that the pump and the wiring to the pump is OK. It is either the
relay, or the circuit that controls the relay that is faulty. See
Testing Relay Circuit below.
Page 138
Fuel Pump and Fuel Tank
3. Connect a voltmeter across relay socket terminals 86
(+) and 85 (-). Briefly crank the starter and check that
there is battery voltage. If not, the ground signal from
the LH control unit to the fuel pump relay is not present.
87
851
878
234-7
186
CAUTION
Use only a digital voltmeter with high input impedance when
testing solid-state components.
NOTE
LH control unit
B7285
Fig. 9.
Fuel pump relay and LH control unit located behind right side
trim panel in front passenger footwell. Inset shows relay terminal designations on relay panel with relay removed.
If the pump does not run with the relay bypassed, then there
is a fault in the fuel pump circuit. Power may not be getting
from the relay panel to the pump, or even from the battery to
the relay panel. Use the wiring diagrams in 371 Wiring Diagrams, Fuses and Relays to check power and ground in the
circuit.
To test fuel pump relay control circuit
1. Remove the fuel pump relay. See Fig. 9 above.
2. Turn the ignition on and check for power at terminal 86
of the fuel pump relay socket. If there is no power then
either the fuel-injection main relay or the wiring from the
main relay to socket 86 of the fuel pump relay panel is
faulty.
NOTE
See 240 Fuel Injection for information on checking the LH
main relay. See 371 Wiring Diagrams, Fuses and Relays for
all LH wiring diagrams.
The LH control unit must get an ignition pulse telling it that the
engine is being cranked or nJnning. This signal comes from
the ignition system. If this signal is not present at the LH control unit, the fuel pump relay will not operate. See 240 Fuel Injection for LH control unit electrical tests.
4. If there is power at relay sockets as described above,
test the relay itself. When battery power is applied to
terminals 85 (-) and 86 (+), the relay should click
closed (pull-down) and there should be continuity between terminals 30 and 87 and between 30 and 87b. If
not, the relay is faulty.
NOTE
The above test in step 4 does not guarantee that the relay is
working correctly under all operating conditions. Sometimes
the relay may work intermittently only when it has been operating for some time.
Checking for Voltage at the Fuel Pump
This test checks to see if the correct voltage is reaching the
pump. To make the test, remove the pump access cover in the
floor of the luggage compartment. With the engine off, run the
fuel pump as described above under Operating Fuel Pump
for Tests. Then measure the voltage across the pump terminals. See Fig. 10.
Voltage at fuel pump with pump running
• at least 11.5 volts
If the voltage is below 11.5 volts, check all wiring connections in the circuit for looseness or corrosion. Clean or tighten
as necessary. If there is no voltage at the pump, check the
wire between the pump and the relay and the ground wire
from the pump to the center crossmember in the trunk.
FUEL PUMP
Page 139
234-8
Fuel Pump and Fuel Tank
Wiring
hamess
Vacuum hose
connection
Fig. 10. Checking for voltage across fuel pump terminals with
pump running and engine off. Roller-type pump shown.
On models with rotor-type pump probe from back of wiring connector.
Testing Turbo Over-pressure Switch
(1985-1988 models only)
87287
Fig. 11. Turbo over-pressure switch used on 1985-1988 Turbo models. Be sure to connect switch wires to terminals 1 and 2, as
shown at arrows.
Replacing Roller-type Pump
The over-pressure switch is mounted under the instrument
panel to the left of the steering wheel, just behind the fuselrelay panel. Fig. 11 shows the switch. The switch is used as a
backup safety device in the event the turbocharger wastegate
malfunctions. If the turbocharger boost pressure exceeds a
safe level, the over-pressure switch interrupts power to the
fuel pump. The tests described below require the use of handheld vacuumtpressure pump.
NOTE
All 1989 and later Turbo models also have an over-pressure
safety feature, although it is handled by the 2.4 LH control unit
instead of a separate pressure switch.
When replacing a roller-type pump, pay close attention to
the installed height and orientation of the pump. Incorrect installation can lead to fuel starvation or pump failure. Be sure to
have new fuel line sealing washers on hand.
10 replace roller-type pump assembly
1. Disconnect the battery negative H cable and cover the
terminal pole on the battery. Remove the fuel pump access cover in floor of luggage compartment. Disconnect the pump wiring.
NOTE
To test turbo over-pressure switch
1. Working beneath the left-hand side of the instrument
panel, disconnect the vacuum hose from the switch
and plug the hose. Attach the pump to the switch using
the piece of hose.
2. With the engine running, slowly increase pressure. The
engine should shut off when the pressure reaches approximately 1 bar (14.5 psi).
3. If the engine does not shut off, turn off the engine and
disconnect the harness connectors from the switch.
Connect an ohmmeter across switch terminals 1 and 2.
With no pressure applied to the switch, there should be
continuity. With 1 bar (14.5 psi) of pressure applied to
the switch, there should be no continuity. If any faults
are found, replace the switch.
FUEL PUMP
On cars with LH 2.4 fuel injection, disconnecting the battery
will erase the control unit's adaptive memory. When the en·
gine is restarted it may operate erratically. The engine must be
driven for at least 30 minutes for the adaptive memory to be
reset.
2. Disconnect the fuel line from the pump. Using an openended wrench, hold the pump still while removing the
dome nut. See Fig. 12.
WARNING
Fuel will be expelled when the fuel lines are disconnected and
the pump is removed. Do not smoke or create sparks. Have
an approved fire extinguisher handy.
Page 140
Fuel Pump and Fuel Tank
234-9
6. To assemble the pump, install the wiring to the supply
CAUTION
Be careful not to damage the fuel pump terminals when loosening the center banjo boll. If a terminal is broken off it is not
repairable and the entire pump must be replaced. A special
wrench is available to reduce the possibility of breaking a
pump terminal. The wrench is Saab Part No. 83 94 330
pump and install the supply pump into the reservoir,
pressing it against the stop.
NOTE
On the supply pump, the white wire goes to the positive (+)
terminal and the black wire to the negative (-) terminal.
7. Install the main pump into the collar and adjust it to the
height shown in Fig. 14. Install the pump with collar into
the reservoir and adjust the total height of the pump assembly to the specification shown in the figure.
Rg. 12. Fuel line being removed from fuel pump.
3. Lift the pump up just enough to disconnect the fuel return line from the fuel reservoir and the wiring from the
supply pump.
B
4. Using a flexible nut driver, loosen the collar mounting
strap. See Fig. 13. Carefully lift out the pu mp.
87290
Main Fuel Pump
• Dimension A
All
• Dimension B
42±2 mm (1.65±.08 in.)
1985-early 1988
(up to VIN J3001527
and J7004073)
225 mm (8 7/8 in.)
Early 1988 and later
(from VIN J3001528
and J7004074)
242 mm (9 1/2 in.)
, 87289-S 17303
Fig. 14. Assembled dimension of main fuel pump in reservoir and rubFig. 13. Fuel pump mounting collar strap being loosened.
ber collar.
5. To disassemble the pump, pull the main pump out of
the reservoir. The supply pump is held with a bracket
and two screws.
FUEL PUMP