Remove the battery cover.

Disconnect the negative cable from the battery.

Remove the air filter

Disconnect the fuel injector connector.

Remove the quick connector.

Remove the fuel distributor.

Fig. 1. Fuel injector and fuel distributor: 1 - quick connector; 2 – fuel distributor; 3 – a clip of a fuel atomizer; 4 - fuel injector; 5 - insulator

If the fuel injector flange or coated fuel distributor element is damaged, it may cause fuel to leak.

Fig. 2. Fuel injector: 1 - fuel distributor element; 2 - flange; 3 - clamp

Remove the fuel injector clip carefully to prevent damage (fig. 2).

Using a deformed fuel injector clip may cause incorrect fuel injector installation and fuel leakage.

After removing the fuel injector, replace the clip with a new one.

Fig. 3. First step of removing the fuel injector clamp

Peel off one side of the fuel injector clamp from the fuel injector flange (fig. 3).

Fig. 4. The second stage of removing the fuel injector clamp

While holding the side of the fuel injector clip that was removed during the first step to prevent it from snapping back into place, remove the other side of the fuel injector clip (fig. 4).

Fig. 5. Final removal of the fuel injector clip

Remove the fuel injector clamp by sliding it axially (fig. 5).

Install

Apply a small amount of clean oil to the new O-ring.

A damaged o-ring can cause fuel to leak.

Be careful not to damage the O-ring when installing the fuel injector.

If there are foreign objects on the connecting part of the fuel injector, the fuel injector and fuel distributor may be damaged.

To prevent damage, clean the connecting part before connecting the fuel injector.

Fig. 6. Installing the fuel injector

Install the fuel injector directly into the hole (fig. 6).

Check that the fuel injector rotates smoothly. If not, install the fuel injector again.

Install the new fuel injector clamp onto the fuel injector and install the retainer on the bottom of the fuel injector connector.

Fig. 7. Installing the fuel injector clamp: 1 - flange

Insert the fuel injector flange into the groove of the fuel injector clamp and slide the fuel injector clamp over the injector, keeping the groove of the fuel injector clamp parallel to the fuel injector flange (fig. 7).

Make sure the fuel injector flange is fully inserted into the groove.

Checking and replacing the injector of the 1.6 l engine

Preparing the car

Remove the lower part of the air filter housing

Mazda 3 fuel injector replacement

Disconnect the wiring harness block from the injector

Mazda 3 fuel injector replacement

Using a tester in ohmmeter mode, we check the resistance of the injector winding, for which we connect the tester leads to the injector contacts

Resistance should be about 14 ohms, otherwise the nozzle needs to be replaced

Also check the rest of the injectors

Using two wires directly from the battery, we briefly apply 12 volts to the injector contacts.

A good injector should have a characteristic click when the valve opens. Replace defective injectors

Replacing nozzles

Preparing the car

Relieve fuel pressure in the fuel line

Disconnect the wiring harness pads from the injectors

Mazda 3 fuel injector replacement

Squeeze the latch and disconnect the fuel line from the fuel rail

Mazda 3 fuel injector replacement

Use a 12 socket wrench to unscrew the fuel rail mounting bolts

Mazda 3 fuel injector replacement

Remove the fuel rail assembly with injectors by pulling up

If one or more injectors remain in the intake piping, the clips of these injectors must be replaced

Mazda 3 fuel injector replacement

Bend the tabs of the latch and remove the nozzle from the fuel rail

Replace the upper O-rings of the injectors each time the fuel rail and injectors are disconnected

Mazda 3 fuel injector replacement

Remove the nozzle retainer

Mazda 3 fuel injector replacement

Pry off the top sealing ring of the injector with a screwdriver and remove it

Mazda 3 fuel injector replacement

In the same way, remove the lower (2) and middle (1) o-rings

Install parts in reverse order

When installing the sealing rings, make sure that they are not twisted

To facilitate the installation of the injector, lubricate the O-rings of the injectors with technical petroleum jelly or gear oil

Checking and replacing the injector of the 2.0 l engine

Preparing the car for the task

Remove the engine trim

Mazda 3 fuel injector replacement

Disconnect the harness block from the injector

Using a tester in ohmmeter mode, we check the resistance of the injector winding, for which we connect the tester leads to the injector contacts.

Resistance should be in the range of 11.5-12.6 Ohm, otherwise we replace the nozzle

Also check the rest of the injectors

Using two wires directly from the battery, we briefly apply 12 volts to the injector contacts.

A good injector should have a characteristic click when the valve opens. Replace defective injectors

Replacing nozzles

Preparing the car

Disconnect the wire blocks from the injectors

Mazda 3 fuel injector replacement

Remove the wire harness holders from the fuel rail

Mazda 3 fuel injector replacement

Mazda 3 fuel injector replacement

Turn the lock and disconnect the fuel line from the fuel rail

Mazda 3 fuel injector replacement

Using a 10 socket wrench, unscrew the bolts securing the fuel rail and remove it complete with injectors by pulling it up

Warning: If one or more injectors remain in the intake manifold, the injectors must be replaced.

Replace the injector O-rings each time you remove the fuel rail or injector

Mazda 3 fuel injector replacement

Bend the tabs of the latch and remove the nozzle from the fuel rail

Mazda 3 fuel injector replacement

Pry off the top sealing ring of the injector with a screwdriver and remove it

Mazda 3 fuel injector replacement

In the same way, remove the lower sealing ring

Mazda 3 fuel injector replacement

The upper and lower injector O-rings are not interchangeable and have different colors

Install parts in reverse order

When installing the sealing rings, make sure that they are not twisted

To facilitate the installation of the injector, lubricate the O-rings of the injectors with technical petroleum jelly or gear oil