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Preparation For Testing

  1. All CIS systems are very sensitive to air leaks. Check condition of rubber boots, hoses and gaskets. Other areas of air leakage are injector "O" rings, cold start valve, oil filler cap and dipstick.
  2. Install pressure gauge to perform fuel pressure tests. Pressure gauge is installed in line between control pressure regulator and fuel distributor. See Fig 1 .
    Fig 1: Pressure Gauge Installation
    G35408
    NOTE: After installation, bleed pressure gauge by opening and closing valve several times.
  3. To operate fuel pump with engine not running, disconnect safety contact switch connector on airflow sensor (if equipped).
  4. Turn ignition on. Place pressure gauge as low as possible in engine compartment, then open and close valve 5 times to bleed gauge. Place valve in open position and hang in convenient location. Turn pump off.