1995 RENAULT MEGANE SCENIC Fuel

ANTIPOLLUTION
Catalytic converter - oxygen sensor
14
CHECKS TO BE MADE BEFORE THE ANTI-
POLLUTION TEST
Ensure:
- the ignition system is operating correctly
(correct spark plugs, correctly set plug gap,
high voltage leads in good condition and
correctly connected).
- the injection system is operating correctly
(supply is correct - check using the XR25).
- the exhaust pipe is correct and is sealed.
- the EGR is operating correctly.
Check the vehicle history if possible (run out of
fuel, lack of power, use of incorrect fuel).
CHECKING ANTI-POLLUTION STANDARDS
Run the engine until the engine cooling fan has
operated twice.
Connect a correctly calibrated four gas analyser to
the exhaust tail pipe.
Keep the engine speed at 2500 rpm for
approximately 30 seconds then let the engine
return to idle speed and note the pollutant values.
CO
≤0.3 %
CO
2≥14.5 %
HC
≤100 ppm
0,97
≤λ≤1.03
1
NOTE : λ = ————
richness
λ>1→lean mixture
λ<1→rich mixture
If, after these tests, the values are correct, the
antipollution system is correct.
If the values are not correct, additional tests must
be carried out:
- Check the condition of the engine (condition
of the oil, valve clearances, timing, etc,...),
- Check the correct operation of the oxygen
sensor (see section 17) ,
- test for the presence of lead (see following
page).
If the test for the presence of lead is positive, en-
sure the vehicle uses two or three full tanks of un-
leaded fuel before replacing the oxygen sensor.
If, after all these tests have been carried out, the
values still do not conform, the catalytic converter
must be replaced. Petrol engine
14-21

STARTING - CHARGING
Alternator
16
REMOVAL
Disconnect:
- the battery,
- the alternator electrical connections.
Remove the mounting bolt for the diesel fuel pipe
retaining bracket and move it to one side.
98837R
Slacken bolt (A) then bolt (B), to just past the
shoulder, while holding the automatic tensioner
plate with a 9 mm wrench (Eg. : FACOM J 151 rat-
chet), then slacken the belt by moving the ratchet
in the direction of the arrow. F 8 Q engine
with AC
98837-1R
Remove:
- the lower timing cover,
- the belt,
- the alternator mounting bolts,
- the alternator.
REFITTING(Special note)
Refitting is the reverse of removal.
The belt is tensioned by moving the automatic
tensioner plate against the stop at bolt (B), wi-
thout forcing it, using a 9 mm wrench (Eg. :
FACOM J 151 ratchet ).
98837-1R1
NOTE : do not refit a belt once it has been remo-
ved.
16-6

STARTING - CHARGING
Starter motor
16
OPTIMA 5800 diagnostic station
CHECKING THE STARTER USING THE DIAGNOSTIC STATION
The starter may be tested using the OPTIMA 5800 diagnostic station, by measuring the battery voltage and
the current used during the starting phase. The following operating faults may be detected:
- battery fault (voltage drops when the starter is activated),
- starter jammed (the current used is too high),
- starter fault (the current used is too low).
To carry out the test the vehicle must be prevented from starting:
- E7J, K7M engines : disconnect the engine speed sensor (on the clutch bellhousing),
- F3R engines : disconnect the engine speed sensor (on the gearbox),
- F8Q engines : disconnect the fuel shut off on the pump and insulate the terminal.
NOTE :
- an open circuit on the engine speed sensor or the ignition creates a fault which is memorised in the injec-
tion computer. Erase this fault using the XR25 (see injection section),
- if the vehicle is fitted with an immobiliser, just lock the doors using the PLIP.
FAULT FINDING
SPECIAL TOOLING REQUIRED
16-10

INJECTION
General
17
E7J engine
1Injection computer
2Coolant temperature sensor (white connector)
3TDC sensor
4Fuel vapour recirculation solenoid valve
5Ignition power module
6Idle speed regulation micromotor
7Throttle position potentiometer
8Absolute pressure sensor
NOTES:
• the injector and the air temperature sensor are integral in the upper section of the throttle body (see sec-
tion 12),
• the pinking sensor is located under the inlet manifold,
• the diagnostic socket is located in the passenger compartment connection unit.
LOCATION OF COMPONENTS
17-7

INJECTION
General
17
K7M engine
1Injection computer
2Pinking sensor
3Coolant temperature sensor
4TDC sensor
5Fuel vapour recirculation solenoid valve
7Idle speed regulation stepping motor
8Throttle position potentiometer
9Air temperature sensor
10Absolute pressure sensor
11Canister
12Coil for cylinders 1 - 4
13Coil for cylinders 2 - 3
14Fuel pump relay
15Anti-interference condenser
16Air filter
17Oxygen sensor
18Power assisted steering pressostat
19EGR solenoid valve
20Vacuum reservoir
21EGR air filter
LOCATION OF COMPONENTS
17-9

INJECTION
General
17
F3R engine
1Injection computer
2Pinking sensor
3Coolant temperature sensor
4TDC sensor
5Fuel vapour recirculation solenoid valve
6Cylinder reference sensor
7Idle speed regulation solenoid valve
8Throttle position potentiometer
9Air temperature sensor
10Absolute pressure sensor
11Canister
12Coil for cylinders 1 - 4
13Coil for cylinders 2 - 3
14Fuel pump relay
15Anti-interference condenser
16Air filter
17Oxygen sensor
LOCATION OF COMPONENTS
17-11

INJECTION
Location of components
17
K7M engine
7Idle speed regulation stepping motor
8Throttle position potentiometer
9Air temperature sensor
10Absolute pressure sensor
99359R3
12Coil for cylinders 1-4
13Coil for cylinders 2-3
15Anti-interference condenser
99365R1
17Oxygen sensor
(tightening torque: 4.5 daN.m)
99355-1R
99361R
5Fuel vapour recirculation solenoid valve
17-13

98900-1R1
INJECTION
Location of components
17
F3R engine
1Injection computer
5Fuel vapour recirculation solenoid valve
99218-1R
2Pinking sensor
(tightening torque : 2.5 daN.m)
12Coil for cylinders 1 - 4
13Coil for cylinders 2 - 3
15Anti-interference condenser
3Coolant temperature sensor (clipped)
6Cylinder reference sensor (see removal in
sub-section "Special notes for sequential in-
jection")
7Idle speed regulation solenoid valve
8Throttle position potentiometer (non-
adjustable)
9Air temperature sensor (clipped)
10Absolute pressure sensor
99238R2
4TDC sensor
99221R
17-15