There is no point in buying those; for a GM you can do the same thing with a
jumper wire. See my site below or www.troublecodes.net for instructions.
If the Check Engine light has been coming on, then there should be a code
stored in memory.
A few '94 and many '95 models are partially OBD II systems and cannot be
read either with a jumper or with one of those cheap code reader devices, a
real scan tool is needed.
Robert Hancock Saskatoon, SK, Canada
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