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Home >> Porsche >> 1983 >> 928 Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Fuel Injection System - BOSCH AFC >> Testing >> Fuel Pressure
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Fuel Pressure

  1. Remove capped nut from test connection on fuel rail without damaging seal. Connect fuel pressure gauge to test connection. Working inside passenger compartment, fold up passenger foot support (if equipped) and unplug fuel pump relay from central electric board.
  2. Fuel pump relay is second box from right side on bottom row on 928S, second box from left in row furthest from fuses on 944. Using jumper wire, connect together terminals 30 and 87 for 928S, 30 and 87b on 944. Fuel pump should run. Fuel pressure should be as specified. If not, replace fuel pump.
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