TM  9-2320-257-24-l COMPRESSION   /  MECHANICAL DIAGNOSTIC    FLOWCHART BATTERY    ClRCUlT    OK STARTER    CIRCUIT    OK ENGINE    NOT  SE!ZED AIR   AND   FUEL  TO ;T OPTIONS 1 DOES  THE   ENGINE  SOUND NORMAL   AND  HAVE  NORMAL VIBRATIONS    AT  ALL  SPEEDS? REV  THE   ENGINE. DRIVE   THE VEHICLE. 1     POSSIBLE PROBLEMS 1 REASON    FOR  QUESTION I I- ]I , The   first  indication    of  a  mechanical problem    is an  abnormal    noise   or vibration. Before   running   other   tests to  check   for  engine    problems,    this   is to  try  to  make   sure   that  you   don’t make   a  bad  problem    worse. INTAKE/EXHAUST FUEL   SYSTEM ENGINE L-l -t, 5 KNOWN   INFO r OPTIONS STUICE-R TEST   14 (Page   2-493) BATTERY    CIRCUIT OK STARTER    CIRCUlT OK ENGINE    NOT  SEIZED AIR   AND   FUEL   TO CYLINDERS FUEL   SYSTEM    OK INTAKE/EXHAUST OK DOES  THE   ENGINE   PASS THE COMPRESSION     UNBALANCE TEST? REASON    FOR  QUESTION If  the  engine   fails  the  cylinder unbalance    test,   it indicates    an individual    cylinder    problem   such   as a  bad  fuel  injector,   excessive blowby.    etc. POSSIBLE PROBLEMS ENGINE KNOWN    INFO TEST   OPTIONS DOES  THE   ENGINE   PASS THE POWER  TEST? St-E/ICE-R    TEST   13 (Page   2-492) REASON    FOR   QUESTION Loss  of  power   can  be  caused   by internal   engine   problems,    fuel system,   air  intake/exhaust, or drivetrain    problems. BATTERY    CIRCUIT OK STARTER    CIRCUIT OK ENGINE    NOT  SEIZED AIR   AND   FUEL   TO CYLINDERS POSSIBLE PROBLEMS ENGINE FUEL   SYSTEM INTAKE/EXHAUST IF  YOU  WERE   SENT   HERE   FROM 2-l  50