Code 54 on 1986 astro with 4.3 how to repair? changed the fuel pump relay still have the problem.
Code 54 indicates a high mixture control solenoid voltage at the ECM going by http://www.angelfire.com/empire/automotivehelp/Astrovan_Trouble_Codes.html#fiftyfour. This is usually a consequence of a shortened M/C solenoid circuit. It can also be caused by a faulty ECM or low voltage in the fuel pump. A mechanic should be consulted to aid in solving this problem.