Page 221
REST POSITION OF AIR FLOW SENSOR PLATE
To check the rest position of the air flow sensor plate,
switch off the ignition (to switch off the fuel pump).
This prevents fuel being injected into the cylinders if the
sensor plate is lifted from its rest position. The top of
the sensor plate should be level with the bottom edge of
the air venturi. This is the highest permissible position for
the sensor plate. A position slightly beneath the lower
edge of the venturi (0.02" /0.5 mm max.) is permissible.
The position should be checked in line with the lever.
OPENING IN THE AUXILIARY
AIR VALVE
A---+
Switch on the ignition. The opening should close completely after about 5 minutes.
If the auxiliary air valve does not close, check the power
supply. If no fault is found, the auxiliary air valveshould
be replaced.
CHECKING THE REST POSITION OF THE SENSOR PLATE
Rest position adjustment is carried out by bending the
loop (A) on the wire underneath the sensor plate. The
air flow sensor must first be dismantled.
VOLTAGE ACROSS THE FUEL PUMP
Remove the round cover plate from the top of the fuel
pump (located in the trunk compartment) and measure
the voltage between the positive and negative terminals
when the pump is operating. The lowest permissible voltage is 11.5 V. Disconnect the terminals connecting the
pump to .the air flow sensor and the warm-up regulator if
these are to be checked later.
ADJUSTING THE REST POSITION OF THE SENSOR PLATE
PERFORMANCE OF AUXILIARY
AIR VALVE
(Checking can only be carried out when the engine is cold.)
Isolate the safety circuit by disconnecting the terminal
on the air flow sensor.
If the "COLD ENGINE CONTROL PRESSURE" (see
below) is also to be checked, the terminals on the warmup regulator should be disconnected to prevent the bimetal strip from warming up.
Check by means of a torch and a mirror that there is a
elliptical opening in the auxiliary air valve.
SA.Ml
MEASURING THE VOLTAGE ACROSS THE FUEL PUMP
240-19
Page 222
FUEL PUMP CAPACITY
Provided that the fuel filter is not clogged and that the
battery is properly charged, the pump capacity can be
checked by measuring the return fuel in the following
way.
Disconnect the return fuel pipe from the fuel distributor.
Connect test pipe 83 93 183 to the fuel distributor and
place the open end in a suitable vessel. Connect the fuel
pump and allow it to run for 30 seconds as follows:
Cl system with safety switch on the air flow sensor
(up to and including early 1977 model):
Remove the switch connector from the air flow sensor.
WARM-UP REGULATOR
Check the warm-up regulator line as follows:
Disconnect the terminal from the warm-up regulator and
connect a voltmeter across the contacts in the connector.
Ensure that the ignition is switched on and that the safety circuit connection at the air flow sensor has been withdrawn. The lowest permissible voltage is 11.5 V.
Cl system with fuel pump relay with pulse sensor
(from early 1977 model):
Remove the fuel pump relay and connect a jump lead
between terminals 15 and 87 in the relay holder.
CHECKING THE WARM-UP REGULATOR LINES
Check that there are no brakes in the coil of the regulator
by connecting a buzzer or test lamp in series with the coil.
If the coil is found to be damaged, the warm-up regulator
should be replaced.
PERFORMANCE AND TIGHTNESS OF INJECTION
VALVES
Switch on the ignition and allow the pump to run.
Measure the quantity of fuel - see specification.
The injection valves can be checked as follows:
1. Remove the rubber bellows from the air flow sensor.
2. Unscrew the injection valves from the inlet manifold
and place them in a suitable container. The fuel lines
should be left connected.
240-20
SAMI
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Page 223
CAUTION
Due to the atomization of the fuel, there is an acute
fire risk when the cold start valve is being tested.
CHECKING THE PERFORMANCE AND TIGHTNESS OF
THE COLD START VALVE
THERMO-TIME SWITCH
:l Switch 6n the ignition an_dremove the plug from
the air flow sensor (up to and including 1976 model)
or connect a jump lead between terminals 15 and 87
in the relay holder (as from 1977 model).
4. Fuel atomization: Lift the lever in the air flow sensor
and check the spray form emitted at the injection valves. If the atomization is poor, see under "Cleaning of
injection valves" for further details.
5. Valve tightness: Switch off the ignition to obtain the
rest pressure. Wipe dry the area around the injection
valve nozzles. Lift the lever and check for leakage. It
should not take less than 15 seconds for a drop to
form. In the case of excessive leakage, see under
"Cleaning of injection valves".
PERFORMANCE AND TIGHTNESS OF COLD START
VALVE
When the engine temperature is below approximately
113°F (+45°C), current is allowed to flow for a certain
period (depending on the temperature) while the starter
motor is running.
Check that the switch closes when the engine is started
by means of connecting a test lamp in series across the
contacts of the cold start valve plug.
It is not possible to make a more accurate check of the
cut-in time or temperature. If the condition of the switch
is at all in doubt, it should be replaced.
PRESSURE READING
General
Connect pressure gauge 83 92 516 as follows:
Disconnect the control pressure line from the fuel distributor and connect the pressure gauge between the fuel
distributor and the line to the control pressure regulator.
Withdraw the plug of the cold start valve and unscrew the
latter from the throttle valve housing, allowing the fuel
line to remain connected.
Connect a wired plug to the cold start valve and connect
the wires to the main beam terminal and body of one of
the head Iights.
Switch on the ignition and disconnect the electrical connuction to the air flow sensor. The fuel-pump is now running. Place the cold start valve in a container and have an
assistant switch the head Iights to main beam for a short
pEiriod (30 seconds max.). Fuel should spray out of the
valve during this period.
Dry the valve nozzle and let the fuel pump run for a further minute. No fuel should pass through the valve during
this time.
CAUTION
Due to the atomization of the fuel, there is an acute
fire risk when the cold start valve is being tested.
PRESSURE GAUGE
240-21
Page 224
'-----
CONNECTION OF PRESSURE GAUGE
REMOVING THE FUEL PUMP RELAY
·-
CAUTION
Up to early model 1977, the safety function governing the operation of the fuel pump is regulated
by means of a switch on the air flow meter. As
from model 1977, the safety function is governed
by a pulse sensor in the pump relay which is actuated by the ignition pulses.
Up to early model 1977: Isolate the safety circuit by disconnecting the terminal at the air flow sensor. Thus, the ·
fuel pump will cut in as soon as the ignition is switched
on.
JUMP LEAD FITTED
Bleed the pressure gauge by repeated opening and closing
of the valve with the pressure gauge directed downwards
and the fuel pump connected.
Cold engine control pressure
lSOLATING
THE SAFETY CIRCUIT
As from later model 1977: Disconnect the fuel pump
relay and connect a jump lead across terminals 30 and 87
in the relay holder. Thus, the fuel pump will cut in.
Carry out this test if poor engine performance has been
experienced during cold starting and the warming up period.
The test can only be carried out when the engine is cold.
The engine should not be run for a longer period of time
(e.g. overnight) before the test can be carried out, to ensure that the engine is at ambient temperature. The engine must not be run before this test.
Open the valve, disconnect the plug at the warm-up regu·lator and switch on the ignition.
Compare the pressure gauge reading with the recommended
pressure given in the temperature/pressure graph. Refer to
the test values in Group 0.
If the values should differ, replace the warm-up regulator.
Warm engine control pressure
Carry out this test when poor performance has been experienced when the engine is war~.
Open tne valve.
Connect the warm-up regulator plug.
Leave the ignition switched on until rest pressure is present.
Refer to the test values in Group 0.
If the value should differ, replace the warm-up regulator.
24~22
SA-S
.«If
Page 225
IDLING ADJUSTMENT (ENGINE SPEED AND CO
VALUE}
Line pressure
Close the valve.
Switch on the ignition.
Refer to the test values in Group 0.
If the line pressure should differ from the recommended
values, this may be due to:
In the case of insufficient line pressure:
Insufficient pressure from the fuel pump
Blockage of the strainer in the tank
Leakage in the fuel line
Line pressure regulator being faulty
In the case of excessive line pressure:
Blockage of the return line
Line pressure regulator being faulty.
For adjustment of the line pressure see under "Mixture
control unit, line pressure regulator".
Run the engine until it is warm and then connect the CO
gauge and the tachometer.
Adjust the idling speed by means of the adjustment screw
located on the by-pass passage at the throttle valve housing.
Leakagetestson the whole system
The test should be carried out after unsatisfactory performance arising from warm-engine starting.
If the engine is cold, the bi-metal strip in the warm-up regulator must be heated and kept warm during the test.
·unplug the connector on the warm-up regulator and replace it with a plug connected directly to the battery.
Open the valve. Switch on the ignition until "warm engine control pressure" is reached, and then switch off the
ignition.
Observe the pressure drop on the pressure gauge. Leakage
can generally be established after 3 or 4 minutes. In cases
of uncertainty, carry out the test for 20 minutes. Refer
to the test values in Group 0.
If the pressure drops too rapidly, the fault can be located
by conducting the test with the valve closed.
If the figures obtained from this test are correct, then
the warm-up regulator (stop valve as from 1978 model)
is faulty.
If the pressure drop is still excessive, the following components could be faulty:
The fuel pump
The fuel distributor
The injection valves
The cold start valve
If the O-ring of the line pressure regulator is damaged,
leakage may occur. For replacement of the O-ring, see
under "Mixture control unit, line pressureregulator".
ADJUSTING THE IDLING SPEED
To adjust the CO value, remove the plug from the small
hole located between the fuel distributor and the rubber
bellows and insert Allen key 8392482.
As from model 1977, the plastic plug in the adjusting
hole must be removed. A suitable tool can be made by
brazing a 0.20 in. (5 mm) self-tapping screw onto a
screwdriver. Grind a fine point on the screw and use the
tool as an extractor. After completing the adjustment
work, reseal the adjusting hole using a red plastic plug.
REMOVING THE PLASTIC PLUG, AS FROM MODEL 1977
SA.1'B
240-23
Page 226
Dismantling and assembly
repairs and adjustments
Turning in a clockwise direction - richer mixture.
Turning in an anticlockwise direction - leaner mixture.
FUEL PUMP
Removal, metal tank up to and including 1979 model
1. Disconnect the battery to prevent flashover and the
risk of fire when the fuel tank has been opened.
2. Roll back the carpet in the trunk compartment (Saab
99 Combi Coupe: Remove the rear floor cover and
floor panel in the luggage compartment), and remove
the circular cover plate on top of the pump mounting.
3. Remove the rubber cover from the pump and disconnect the electric terminals at the pump.
4. Disconnect the fuel line from the pump. Hold the
pump by means of an open-ended spanner when loosening the connection.
ADJUSTING THE CO-VALUE
CAUTION
Remove the Allen key from the adjustment screw
after each adjustment. If the key is left in the screw
and the engine revved up, the lever could be damaged.
I
DISCONNECTING THE FUEL LINE
5. Using tool 8392433, turn the pump mounting anticlockwise to the nearest groove, to unlock the bayonet
socket. Lift out the pump unit and save the 0-ring.
FITTING A NEW PLASTIC PLUG
NB! As from model 1976:
If the idling speed is erratic or if difficulty is encountered in reducing the idling speed, check the
setting of the overn.J~.valve.
See section 254.
TURNING THE FUEL PUMP
Tool8392433
240-24
SAAB
Page 227
Assembly, metal tank
Assemble the pump unit as shown in the figure.
Note the following:
a. Rotate the pump in the mounting so that none of the
electric connections are in line with the wide tongue
of the bayonet socket which is equipped with a locking
groove. If this is neglected, the electric connection will
be in the way of the fuel line.
b. Rotate the splash guard so that the indent in it is to
the right, looking towards the front of the car. The
wide tongue of the bayonet socket equipped with a
locking groove must point towards the front of the
car.
LIFTING OUT THE FUEL PUMP
te
NOTE
The pump can only be removed in one position, as
one of the bayonet tongues are wider than the others.
6. Suitably cover the tank opening.
Dismantling, metal tank
Releasethe clips and remove the splash guard and pump
mounting from the pump.
S41CJ3
MOUNTING POSITION OF THE SPLASH GUARD
A. Wide bayonet tongue, equipped with a locking groove
B. Driving direction of the car
C. Splash guard indent
c. The distance from the bottom of the splash guard to
the top of the pump mounting should be 8.82" (218
mm).
FUEL PUMP, DISMANTLED
1. Bayonet socket
2. Adapter
3. Fuel pump
4. Splash guard with suction strainer up to and incl. model 1976
5. Splash guard with suction strainer as from model 1977
.
I
240-25
Page 228
4. Detatch the fuel pipes from the pump. Use an openended spanner to hold the pump steady while loosening the banjo connections.
E
E
co
N
S 5632
5. Use a jointed screw driver to undo the pump mounting clamp.
HEIGHT POSITION OF THE SPLASH GUARD
............
Installation, metal tank
1. Place the O-ring over the tank opening and mount the
pump unit. The pump unit can only be fitted in one
position owing to the bayonet socket tongue being
wider than the others. The wider tongue is equipped
with a locking groove.
2. Tighten the pump unit by means of tool 8392433.
3. Connect the electric terminals and the fuel line to the
pump and replace the rubber cover. Hold the pump
by means of an open-ended spanner when tightening
the connection screw ..
4. Fit the cover plate for the pump opening in the floor
and fit the carpet (Saab 99 Cambi Coupe: Fit the floor
panel and rear floor cover).
5. Connect the battery.
Removal (plastic tank 1980 model)
1. Disconnect the battery
2. Remove the rear floor panel in the luggage compartment and remove the valve cover from above the fuel
pump.
3. Disconnect the fuel pump's electrical connections.
240-26
SAAB
6. Lift out the pump.
Page 229
4
2
3
5
3. Install the pump unit in the tank as follows:
Tilt the+ electrical connection to the left (as seen
from the direction of movement of the car).
Tilt the suction strainer inlet 45° backwards to the
right (as seen from the direction of movement of
the car).
Removal is in the reverse order.
@-6
.1. Clamp
2. Sealing collar
3. Pump support
4. Fuel pump
5. Bellows
6. Suction strainer
7. Splash guard
8. Fuef return pump
Installation (plastic tank, 1980 model)
1. Position the pump on the mounting so that the distance between the base of the suction strainer and the
upper edge of the rubber mounting is 236 mm (9.2 in.)
2. Check that the fuel return pipe is connected to the
splash guard holder in the bottom of the fuel tank.
SAAB
240-27
Page 230
Non-return valve (as from 1978 model)
The non-return valve in the fuel pump outlet pipe can be
removed using a specially shaped screwdriver (see illustration).
FUEL ACCUMULATOR
UP TO AND INCL. 1979 MODEL
FUEL ACCUMULATOR
AS FROM 1980 MODEL
S 6617
Installing the non-return valve
Installation
Avoid gripping the valve too tightly, as this may damage
it.
Torque
0.4-0.6 Nm (2.9-4.3 ft. lb., 4-6 kpcm)I
1. Mount the accumulator on the bracket.
2. Connect the fuel lines. The line from the fuel pump
should be fitted to the connection nearest to the edge
of the fuel accumulator.
Make sure that the fuel line from the pump is not in contact with the body.
REPLACING THE FUEL FILTER
1. Clean the area around the two connections.
2. Hold the filter by means of the hexagons on the filter
and nipple and disconnect the fuel lines. Remove the
filter.
FUEL ACCUMULATOR
Removal
1. Clean the area around the fuel connections.
2. Disconnect the connections and remove the fuel accumulator.
CAUTION
Avoid loosening the nipple on the outlet side to prevent aluminium swart from the threads entering the
system.
3. Mount the new filter with the arrow pointing in the direction of flow and connect the fuel line.
240'-28
SA.Ml