TM 10-3930-669-20 5.  EXCESSIVE SMOKE (CONT). KNOWN INFO TEST OPTIONS Fuel filter OK. Air filter OK. Visual inspection. POSSIBLE PROBLEMS REASON FOR QUESTION Air intake system leaking. Fuel connections leaking. Fuel injector(s) faulty. Air intake obstructed. Fuel injector pump faulty. Intake   air   leaks   can   allow   too much air in the fuel air mixture. KNOWN INFO TEST OPTIONS Fuel filter OK. Air filter OK. Air intake system not leaking. Visual inspection. POSSIBLE PROBLEMS REASON FOR QUESTION Fuel connections leaking. Fuel injector(s) faulty. Air intake obstructed. Fuel injector pump faulty. Loose/leaking    fuel    lines    could introduce air into the fuel resulting  in  too  much  air  in  the fuel air mixture. ¬ ¬ 2-76