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Home >> Porsche >> 1987 >> 928 Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Fuel Injection System - BOSCH LH >> Testing >> Test 16 - Fuel Injectors
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Test 16 - Fuel Injectors

  1. If poor power output is reported (too low at full engine load), cross section size of injector pintle could be restricted by carbon. For this test the ring line is lifted and the fuel injectors held in measuring glasses with help of a new injector installed for comparison.
  2. Remove LH fuel control unit plug. Remove plug "W" on CEB. Apply ground to terminal No. "W12" and 12 volts of battery voltage to terminal No. "W13". Bridge terminals No. 30 and 87 on fuel pump relay No. XX. Difference between all fuel injectors must not exceed 10% by volume. If difference is exceeded, replace injectors.
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