1990 Chevy Silverado ECU and ingnition mod

1990 CHEVROLET SILVERADO
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JOHN DAWSON
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  • 1 POST
Engine Performance problem
1990 Chevy Silverado V8 Four Wheel Drive 240000 miles

Truck idles fine with EST disconected timed at 0 Hook up ECM and it misfires,lopes and dies Ecm showes code 42 so I replaced ignition module and pick-up coil No change so I replaced ECM No change Showing code 42 on new ECM
Feb 22, 2010 at 6:10 AM
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DOCFIXIT
  • ✓Experienced Mechanic
  • 18,828 POSTS
Think one of EST wires has short to ground. Ohm check to ground
Feb 22, 2010 at 7:58 AM
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