DIESEL EXCESSIVE EXHAUST SMOKE ROUGH RUNNING AFTER COLD START. Pontiac LeMans 1983

For 1990-2009 cars

# DIESEL EXCESSIVE EXHAUST SMOKE ROUGH RUNNING AFTER COLD START

#### VEHICLES AFFECTED: 1980-83 VEHICLES EQUIPPED WITH OLDSMOBILE PRODUCED DIESEL ENGINES DIESEL ENGINES THAT EXHIBIT EXCESSIVE EXHAUST SMOKE AND RUN ROUGH AFTER COLD STARTING MAY USUALLY BE CORRECTD BY DYNAMIC TIMING. IF TIMING DOES NOT CORRECT THIS CONDITION CHECK THE HOUSING PRESSURE COLD ADVANCE (HPCA) FOR PROPER OPERATION (1981 THRU 1983 MODELS). ALSO CHECK FOR A STICKING ADVANCE PISTON IN THE INJECTION PUMP (1980 THRU 1983 MODELS). TO CHECK FOR A STICKING ADVANCE PISTON PUSH IN ON THE BOTTOM OF THE FACE CAM LEVER ON THE RIGHT SIDE OF THE INJECTION PUMP. THIS WILL RETARD THE TIMING AND CAUSE THE ENGINE TO RUN ROUGH IF THE ADVANCE PISTON IS FREE. IF THERE IS NO CHANGE, THE PISTON IS STICKING.

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