Mazda X-5. Manual - part 27

EMISSION SYSTEM 

01–16–11

01–16

• New quick release connectors are fitted with a 

checker tab that prevents improper fit. This 
checker tab cannot normally be removed. When 
the quick release connector is properly connected 
to the connection point, the lock is released and 
the checker tab comes off. Due to this, it can be 
verified that the quick release connector is 
completely connected.

End Of Sie

PURGE SOLENOID VALVE FUNCTION [LF]

E5U011618744N01

• Adjusts the amount of evaporative gas to be introduced to the intake air system.

End Of Sie

PURGE SOLENOID VALVE CONSTRUCTION/OPERATION [LF]

E5U011618744N02

• Installed on the air hose.

• Consists of a coil, spring and plunger.

• Opens and closes the passage in the solenoid 

valve according to the purge solenoid valve 
control signal (duty signal) from the PCM to 
control the amount of evaporative gas to be 
introduced to the dynamic chamber according to 
engine operation conditions.

• The signal sent from the PCM energizes the coil 

and it becomes magnetized, pulling the plunger. 
The passage between the ports opens when the 
plunger is pulled, and evaporative gas is 
introduced to the intake air system according to 
intake manifold vacuum.

End Of Sie

CHECKER TAB

CONNECTION POINT

EPU113ZT4610

FROM CHARCOAL 
CANISTER

TO DYNAMIC 
CHAMBER

: FLOW OF EVAPORATIVE GAS

E5U116ZW5042

EMISSION SYSTEM 

01–16–12

FUEL-FILLER CAP FUNCTION [LF]

E5U011642250N01

• If the evaporative gas passage is closed for some reason, the fuel filler cap prevents the generation of positive 

or negative pressure in the fuel tank, protecting it from deformation.

End Of Sie

FUEL-FILLER CAP CONSTRUCTION/OPERATION [LF]

E5U011642250N02

• Consists of a positive pressure valve, negative pressure valve, spring, and O-ring.

• When there is positive pressure in the fuel tank due to evaporative gas, the evaporative gas is released into the 

atmosphere. When there is negative pressure, air is introduced to the fuel tank.

• The positive pressure valve and negative 

pressure valve opening pressures are higher than 
the check valve (two-way) built into the rollover 
valve, therefore the positive and negative 
pressure valves are normally not open.

End Of Sie

ROLLOVER VALVE FUNCTION [LF]

E5U011642720N03

• The rollover valve prevents fuel flow into the evaporative gas passage during sudden cornering or vehicle 

rollover.

End Of Sie

ROLLOVER VALVE CONSTRUCTION/OPERATION [LF]

E5U011642720N04

• The rollover valve cannot be removed or installed as it is built into the fuel tank.

• The rollover valve consists of a float, and spring.

• The rollover valve utilizes a combination of float weight, spring force, and buoyancy. When the float is sunk in 

the fuel, the float (valve) closes to block the sealing surface of the passage.

End Of Sie

SPRING

O-RING

POSITIVE PRESSURE VALVE

NEGATIVE PRESSURE VALVE

E5U116ZS5900

SPRING

FLOAT

VEHICLE LEVEL

FLOW OF EVAPORATIVE GAS

FUEL LEVEL

ROTATED 180

°

E5U116ZS5901

EMISSION SYSTEM 

01–16–13

01–16

FUEL SHUT-OFF VALVE FUNCTION [LF]

E5U011642990N01

• The fuel shut-off valve prevents fuel from flowing to the charcoal canister during tight turns or vehicle rollover.

• The fuel shut-off valve releases evaporative gas to the charcoal canister.

• During refueling, the fuel shut-off valve closes to prevent a fuel overflow.

End Of Sie

FUEL SHUT-OFF VALVE CONSTRUCTION/OPERATION [LF]

E5U011642990N02

• The fuel shut-off valve is built into the fuel tank.

• The fuel shut-off valve mainly consists of a valve, float, spring, and by-pass valve.

• During refueling or due to fuel sloshing, the float 

is flooded with fuel and the floating force causes 
the valve to close. Also, during vehicle rollover, 
the valve closes due to balance between the float 
gravity and spring.

End Of Sie

CHARCOAL CANISTER FUNCTION [LF]

E5U011613970N01

• The charcoal canister contains activated charcoal that temporarily absorbs evaporative gas.

End Of Sie

CHARCOAL CANISTER CONSTRUCTION/OPERATION [LF]

E5U011613970N02

• Installed on the rear of the fuel tank.

• During purge solenoid valve operation, 

atmosphere enters the charcoal canister from the 
atmospheric orifice to entirely flood the activated 
charcoal and release the evaporative gas.

End Of Sie

VALVE

FLOAT

SPRING

E5U116ZS5006

TO PURGE 
SOLENOID VALVE

TO EVAP SYSTEM LEAK 
DETECTION PUMP

TO FUEL 
TANK

EPU116ZT4502

EMISSION SYSTEM 

01–16–14

EVAPORATIVE EMISSION (EVAP) SYSTEM LEAK DETECTION PUMP FUNCTION [LF]

E5U011618581N01

• The internal pump pressurizes the emission system by pumping air to check clogging and leakage in the 

emission system.

End Of Sie

EVAPORATIVE EMISSION (EVAP) SYSTEM LEAK DETECTION PUMP CONSTRUCTION/OPERATION [LF]

E5U011618581N02

Structure

• Orifice

— Has a 0.5 mm {0.02 in} hole

• Pump

— Force-feeds air to the orifice and the EVAP lines

• Heater

— Removes moisture inside the pump

• Change over valve

— Operated by a solenoid valve to switch air passages

Operation
Evaporative system monitor is not operated

• The passage between the canister and the air 

filter is connected.

B6U0116S028

SOLENOID IS OFF AND PUMP IS NOT OPERATED

DURING PURGE SYSTEM OPERATION

FROM AIR 
FILTER

TO CHARCOAL 
CANISTER

CHANGE OVER VALVE
(CLOSED)

EVAP SYSTEM LEAK 
DETECTION PUMP

: AIR FLOW

B6U0116S017