1993 Other GMC Models constant check engine light

1993 GMC
61,468 MILES • 6 CYL • 2WD • AUTOMATIC
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JUNKSTER
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  • 1 POST
truck has constant check engine light and will not put any codes out of the computor. i checked it at the aldl connector, nothing, not even a 12. tried to clear codes by unhooking battery and still same thing.
engine will crank up, but idles very low and when you try to give it gas or put it in gear to move it , it stalls out
Mar 31, 2010 at 8:09 AM
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HMAC300
  • ✓ASE Certified Mechanic
  • 48,601 POSTS
  • ASE Certified Mechanic
as we don't know if you are trying to get the code correctly this is the way it's done on your vehicle. cross only the A & B on the ALDL. turn the key on without starting the engine. and count the flashes, like 1 then 2 that equals a code 12. If you go to trouble code definitions and OBD 1. If it still doesn t' give you a code then check for bad grounds. That should giv eyou something.
Apr 2, 2010 at 3:19 PM
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