cause of service engine soon light on a 1989 buick park ave
Many, many things. Scan for codes to pinpoint the issue down to a few. You also have many choices.....A local auto parts store can do it for free, or you can purchase a scan tool for $25, or take it to your mechanic. Post the 4 digit code back here, and we can help further.
When having it scanned remind them it's OBD I. You'll have a two digit trouble code(s). HTH. -Jim
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