Diagnosis Of Diesel Engine - GMC G Service Manual

DIAGNOSIS OF
DIESEL ENGINE
MOST LIKELY/POSSIBLE CAUSES
X = LIKELIEST CAUSES
• = POSSIBLE CAUSES
G ASKET BLOW -BY O R SEA L LEA K A G E
VALVE LE A K A G E
B RO KEN. SC O R ED O R W ORN PISTONS/RINGS
IN CO RRECT MAIN O R R O D BEARING C LEA R A NCE
DAMAGED CRANKSHAFT O R MAIN/ROD BEARINGS
DAMAGED/WORN CAMSHAFT LO B E S
FA U LTY LIFTER O R GUIDE P LA TE
FA U LTY PUSHRO D O R R O C K ER ARM
WORN/MISALIGNED TIMING G EA R S. CHAIN O R K EY(S)
O IL CHANGE INTERVAL
EXTERNAL INJECTION PUMP TH R O TTLE LINKA G E
TIMING R ETA R D ED
TIMING ADVANCED
LO NG ID LE PER IO D S
C R A C K ED CYLINDER HEAD O R W ALL
MISSING PRECHAM BER(S)
IMPROPER STARTING PR O C ED U R ES
DFRRIS/F1 llin IN P.YI INDFRISI
ELE C TR IC A L/E M IS S IO N S
INOPERATIVE GLOW PLUG S
FA U LTY GLOW P LU G CONTROLLER/IP W IRE GRO UNDS
INOPERATIVE GLOW PLU G C O N TRO LLER /R ELAY
SH O R TED O R O PEN GLOW PLU G INHIBITOR SW ITCH
NO VO LTA G E TO C O N TR O LLER (K E Y O N )
E G R VALVE STU C K O PEN
E P R VALVE STUCK C LO S E D
FA U LTY EG R /EPR SOLENO IDS. ECM . O R MAP SENSO R
MISADJUSTEP O R FA U LTY TH R O TTLE POSITION SW ITCH
HOUSING PRESSU R E C O LD ADVANCE SO LENO ID O R SW ITCH
CRANKCASE DEPRESSION SYSTEM H O SE CONNECTIONS
MISADJUSTEP O R FA U LTY VACUUM R EG ULA TO R VALVE
TRANSMISSION CO N VERTO R D O ES NOT A PPLY
FA U LTY VACUUM PUMP 1 21" H G MIN.)
FA III TV F N R IN F S P F F f l S F N S f lR
AIR SYSTEM __________________________
RESTR IC TED AIR INTAKE DUCTING O R MANIFOLD
HIG H EXHAUST B A C K P R ESSU R E___________
THIN AiR IN H O T W EATHER O R HIG H ALTITUDE
C D PLU G G ED AIR FILTE R ___________________
O LO W AMBIENT TEM PERATURE
J r j H IR H A M R IF M T T F M P F R A T I I R F ____________________
C O