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Home >> Nissan-Datsun >> 1986 >> Stanza GL, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Fuel Injection System - BOSCH AFC >> Testing >> Fuel Pressure
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Fuel Pressure

CAUTION: Constant fuel pressure is maintained in fuel lines and component parts at all times. Relieve pressure before attempting to open system for testing. Do not allow fuel to flow onto engine or electrical parts or allow an open flame in area while testing fuel system components.
  1. Start engine and disconnect Black harness connector of body harness. This is located under assist seat. After engine stalls, crank engine 2 or 3 times. Turn ignition off. Connect harness connector of body harness.
  2. Remove fuel filter-to-fuel rail hose and connect a pressure gauge using a "T" fitting. Start engine and read fuel pressure at idle. If pressure is not as specified, replace pressure regulator and repeat test.
  3. Disconnect vacuum line from fuel pressure regulator and connect a hand vacuum pump. Connect pin of body harness under assist seat to ground with jumper wire. See Fig 1 . Turn ignition on.
    Fig 1: Connect Pin Of Body Harness With Jumper Wire
    G50A08464
  4. As vacuum is applied to pressure regulator, pressure reading should decrease. See FUEL PRESSURE SPECIFICATIONS  table. If pressure and vacuum readings do not conform to specifications, replace fuel pressure regulator.
FUEL PRESSURE SPECIFICATIONS

Condition: In. Hg Pressure: psi (kg/cm2 )
Idle (1) 30 (2.1)
0 36-37 (2.5-2.6)
5 33-35 (2.3-2.5)
10 31-32 (2.2-2.3)
15 29-30 (2.0-2.1)
20 26-28 (1.8-2.0)
(1) Vacuum hose connected at pressure regulator.