LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Daihatsu >> 1992 >> Charade SX >> Repair and Diagnosis >> External Pages >> Different car >> Section 1 (Engine Controls - Basic Testing) >> Fuel System >> Fuel System Pressure Test
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Fuel System Pressure Test

WARNING: This page is about a different car, the 1990 Daihatsu Rocky and 1990 Daihatsu Charade. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Before testing fuel pressure, check all fuel delivery and return lines for leaks.
  1. Ensure battery is fully charged and disconnect negative battery cable. Relieve fuel pressure. Remove union bolt and 2 gaskets.
  2. Install Fuel Pressure Gauge (SST 09268-87701-000) on No. 1 fuel hose of fuel filter using new gaskets. See Fig 1 . Tighten retaining bolt to 25-35 ft. lbs. (34-47 N.m). Wipe off excess gasoline.
  3. Install Sub-Harness (SST 0991-87702-000) on 6-pin check connector located near top of transaxle. Install jumper wire between "F" terminal and ground terminal. See Figure .
  4. Install negative battery cable. Turn ignition on and note fuel pressure. Fuel pressure should be within specification. See FUEL PUMP PRESSURE SPECIFICATIONS  .
  5. If pressure reading exceeds specification, check for restricted fuel return line or line between surge tank and pressure regulator. If no restricted lines exist, check pressure regulator operation. For pressure regulator testing, see I - SYSTEMS/COMPONENT TESTING article.
    Fig 1: Checking Fuel System Pressure
    G90G16564Courtesy of DAIHATSU MOTOR CO. LTD.
  6. If fuel pressure is less than specification, check for restricted fuel lines or fuel filter. Check for defective pressure regulator or fuel pump. For component testing, see I - SYSTEMS/COMPONENT TESTING article.
  7. Turn ignition off, wait 3 minutes and note residual fuel pressure. Residual fuel pressure should exceed 26 psi (1.8 kg/cm2 ). If pressure is less than specification, check for leaking fuel lines. If no leaking fuel lines exist, check for defective fuel injectors, cold start injector, pressure regulator or fuel pump check valve. For component testing, see I - SYSTEMS/COMPONENT TESTING article.
  8. Remove sub-harness and jumper wire from 6-pin check connector and install terminal cap. Start engine and warm to normal operating temperature. Note fuel pressure with engine idling. Fuel pressure should be within specification. See FUEL PUMP PRESSURE SPECIFICATIONS  .
  9. If fuel pressure exceeds specification, check vacuum hose to pressure regulator for restrictions. If no restriction or system abnormality exists, replace pressure regulator.
  10. Disconnect negative cable and remove test equipment. Reinstall union bolt with new gaskets. Tighten union bolt to 25-35 ft. lbs. (34-47 N.m). Wipe off excess gasoline. Reconnect battery cable. Operate and check for leaks.
FUEL PUMP PRESSURE SPECIFICATIONS

Application Specification psi (kg/cm2 )
Charade
With Ignition On (Engine Off) (1) . 37.0-45.5 (2.6-3.2)
Engine At Idle (2) 41.2 (2.9)
Residual Pressure 35.5 (2.5)
Rocky
With Ignition On (Engine Off) (1) 33-40 (2.3-2.8)
Engine At Idle (2) 36.3 (2.6)
Residual Pressure 25.6 (1.8)
(1)
Check pressure with sub-harness installed on 6-pin check connector located near top of transaxle and jumper wire installed between "F" terminal and ground terminal.
(2)
Check with sub-harness and jumper wire removed from 6-pin check connector and terminal cap reinstalled on 6-pin check connector.
scientia non olet · About LEMON Manuals