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Home >> Audi >> 1990 >> 100 Base, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests >> Fuel System >> Fuel Control (Cis MOTRONIC) >> Residual Pressure
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Residual Pressure

  1. This procedure is only required for hot start problems. Connect Fuel Pressure Tester (VW 1318) as previously described in FUEL SYSTEM PRESSURE. See Figure . Open fuel pressure tester valve. Using Remote Control (US 4480/3), as previously connected in step 2) of FUEL SYSTEM PRESSURE, energize fuel pump for 5 seconds. Note fuel pressure drop over time period. Fuel pressure should not drop more than 2 psi in 10 minutes.
  2. If fuel pressure drop is greater than 2 psi in 10 minutes, inspect fuel pump check valve, airflow sensor plate free play, and sealing rings on fuel distributor and fuel lines.
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