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Home >> Ford >> 1987 >> Cutaway 6.9 1 >> Repair and Diagnosis >> Engine Performance >> System >> Fuel Injection System - 6.9L Diesel >> Trouble Shooting >> Engine Knocks
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Engine Knocks

  1. Check engine front drive components for proper operation. If okay, go to next step. If not okay, service or replace as necessary.
  2. Verify that engine is not overheating. If not overheating, go to next step. If engine overheats, service cooling system.
  3. Loosen each injector line nut (one at a time) while engine is running. If engine knock is isolated to specific cylinder(s), go to next step. If engine knock is not isolated, go to ENGINE PERFORMANCE DIAGNOSIS  .
  4. Check injection nozzle fuel line(s) for kinks or restrictions and test injectors. See INJECTORS TEST  . If line(s) and injector(s) are okay, go to ENGINE PERFORMANCE DIAGNOSIS  . If not okay, replace line(s) and/or clean or replace injector(s).
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