Jerry,
Just do a search on a code reader, there are several methods of obtaining the trouble codes. I am not familiar with pre-ODBII cars, but as I understand there is a method of hooking up a light to the connector and counting the blinks to determine the trouble code. ODBII cars have a scanner you plug in and it gives a code number. I have seen several posts on people building ODBI code readers. Good luck.
Brian

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Brian W. Heitman

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