1995 RENAULT MEGANE SCENIC check engine

99366R
FUEL SUPPLY
Supply pressure
13
K7M engine
Fit the 0 ; 10 bars pressure gauge and the hose
Mot. 1311-01.
Shunt terminals (3) and (5) on the fuel pump relay
located in the engine fuse box (see diagram on
page 13-2).
The pressure should be 3 bars ± 0.2.
When a vacuum of 500 mbars is applied to the
pressure regulator, the fuel pressure should be
2.5 bars ± 0.2.
CHECKING THE PUMP SAFETY VALVE (under the
same conditions as previously)
Shunt terminals (3) and (5) of the fuel pump relay
(see diagram on page 13-2).
When the fuel return pipe is clamped briefly, the
pressure should stabilise between 4.5 and 7.5
bars.
13-13

FUEL SUPPLY
Supply pressure
13
CHECKING THE FUEL SUPPLY PRESSURE
SPECIAL TOOLING REQUIRED
Mot. 1311-01 Fuel pressure test kit (with 0 ;+
10 bars pressure gauge included)
99217R1
Disconnect the rear fuel pipe.
Fit the three way valve (1) from tool Mot. 1311-01
and connect the 0 ; + 10 bars pressure gauge.
Shunt terminals (3) and (5) of the fuel pump relay
located in the engine fuse box.
The pressure should be 3 bars ± 0.2.When a vacuum of 500 mbars is applied to the
fuel pressure regulator, the pressure should be
2.5 bars ± 0.2.
CHECKING THE PUMP SAFETY VALVE (under the
same conditions as previously)
Shunt terminals (3) and (5) of the fuel pump relay
(see diagram on page 13-2).
When the fuel return pipe is clamped briefly by
the two position valve, the pressure should
stabilise between 4.5 and 7.5 bars.
F3R engine
13-14

DIESEL EQUIPMENT
Idle speed settings
13
These adjustments must be made when the engine is warm, after the cooling fan assemblies have operated at
least twice.
99337R3
ADJUSTING THE IDLE SPEED AND THE RESIDUAL
FLOW (anti-stall)
Slacken the residual flow screw two turns and
check that the load lever is touching the screw.
Adjust the idle speed to 825 ± 25 rpm using screw
(1).
Fit a 4mm shim between the load lever (2) and
the residual flow screw (3).
Adjust the engine speed to 1 150 ± 25 rpm using
the residual flow screw (3).Remove the 4 mm shim then accelerate sharply
twice.
Check the idle speed setting is correct; if necessary
adjust the idle speed again and recheck the
residual flow setting.
The idle speed and anti-stall function must be set
correctly since they have a direct effect on engine
behaviour at idle speed and during deceleration
(hesitation, idle speed remains operative, etc...).
13-20

DIESEL EQUIPMENT
Idle speed settings
13
ADJUSTING THE FAST IDLE SPEED
Set the separate idle speed lever (4) against the
fast idle screw (5), then adjust the engine speed to
950 ± 25 rpm using this screw (5).
ADJUSTING THE POSITION OF THE FAST IDLE
CABLE GRIP
(when the idle speed and residual
flow settings are correct )
Check that the separate idle speed lever (4) is
against the idle speed screw (1).
Hold the cable taut.
Position the cable grip at a distance of :
-6 mm
± 1 (without air conditioning)
from lever (4)
-2 mm ± 1 (with air conditioning)
from lever (4)
NOTE : vehicles fitted with the air conditioning
option are fitted with a fast idle control
diaphragm operated pneumatically by a solenoid
valve. Fast idle is obtained during post-heating or
when air conditioning is selected (see operating
diagram in the pre-heating section).
ADJUSTING THE DECELERATION DAMPER (6)
When the adjustments above have been made,
the deceleration damper must be adjusted as
described below.
Slacken screws (7) to release the lever (A).
Fit a 1 mm shim between the deceleration damper
and the lever (A).
Push lever (A) on the deceleration damper to the
stop.
Ensure the load lever (2) remains in contact with
the residual flow screw (3).
Tighten the screws (7) in this position.
Remove the adjusting shim and ensure there is
contact between the load lever (2) and the
residual flow screw (3).
13-21

DIESEL EQUIPMENT
Pump - timing
13
CHECKING THE PUMP TIMING
In place of the plug (1) insert the dial gauge
mounting Mot. 856 and attach a dial gauge with
socket.
99336R
Zero the dial gauge to BDC on the injection pump
piston.
Immobilise the engine using tool Mot. 1054. To do
this, turn the engine so that the camshaft sprocket
index is aligned with the timing cover reference
mark.
DI1303-1
99183R
Check the pump piston lift shown on the dial
gauge ; it should be 0.82 ± 0.04 mm. If it is not,
rotate the pump to obtain the required piston lift.
IMPORTANT : after tightening the pump
mounting bolts, turn the engine over twice.
Immobilise the engine once more to check the
pump timing.
13-27

DIESEL EQUIPMENT
Pre-post-heating unit
13
FAULT FINDING
3. There is no fast idle when engine is cold (with air conditioning option)
TEST SOLUTION
Run the air conditioning.
• The fast idle operates
• The fast idle does not operate.Check the connections at the pre-post-heating unit
(connector C).
Ensure continuity between track C3 of connector (C)
and track 1 on the solenoid valve.
Replace the pre-post-heating unit (ensure the
warning light operates correctly when the ignition is
turned on).
If the fast idle solenoid valve opens the pneumatic
circuit, repair the circuit between the vacuum pump,
the solenoid valve and the diaphragm.
If the solenoid valve does not open the circuit,
measure the voltage between the 2 tracks on the
solenoid valve connector.
•12 volts
Replace the solenoid valve after testing the
connections.
•0 volt
Ensure the following continuities :
- between track 2 on the connector and earth,
- between track 1 and track C3 of the pre-post-
heating unit.
13-34

DIESEL EQUIPMENT
Pre-post-heating unit
13
FAULT FINDING
4. Engine operation fault (difficulty in starting, idle speed unstable, noise...)
Check:
- the feed to the pre-post-heating unit :
•+before ignition at connector A.
•+after ignition on track B1 of connector C.
•earth on track C2 of connector C.
- at the pump connector, the resistance of the ALFB solenoid valve (between earth and track
A1) : 7Ω ± 0.5,
- the coherence of the temperature reading given by the coolant temperature sensor,
Temperature (°C) 25 80
Resistance (Ω) 2 610 to 2 990 310 to 350
- the adjustment and operation of the post-heating microswitch,
- the coherence of the open or closed status of the altimetric capsule switch according to the altimetric
pressure of the test site (the switch should be closed for a pressure > 925 ± 20 mbars).
If the fault persists carry out a complete re-adjustment of the pump.
13-35

PUMP
Brake assistance vacuum pump
13
Renew the drive dog systematically when
replacing the pump.
CHECKING
Engine warm, at 4 000 rpm, the minimum vacuum
should be 700 mbars (525 mmHg) in 3 seconds.
SPECIAL TOOLING REQUIRED
M.S. 870 Vacuum gauge
PRJ1303
F8Q engine
13-41