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Home >> Mazda >> 1994 >> MX-3 L4-1598cc 1.6L DOHC >> Repair and Diagnosis >> Powertrain Management >> Tune-up and Engine Performance Checks >> Fuel Pressure >> Testing and Inspection >> Line Pressure
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Line Pressure


WARNING: Before performing this procedure, release fuel pressure.

NOTE: Obtain audio anti-theft access code before disconnecting battery cables.

1. Disconnect negative battery terminal.


View: Typical Fuel Pressure Gauge Installation:





2. Install pressure gauge as shown.
3. Reconnect battery.


Data Link Connector:





4. Connect data link connector terminals F/P and GND with jumper wire.
5. Turn ignition "ON" and check line pressure. It should be 260 - 320 kPa (37 - 47 psi).

If pressure is low:
- Check pump maximum pressure. If as specified, fuel line or filter may be clogged or restricted.

If pressure is high:
- Replace pressure regulator.
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