I had that problem once and did all the usual things.... it turned out it was a vacuum leak for me... well the hose had rotten apart... right below and behind... or in front  the distributor... hooked it back up and didn't miss a beat after that
-Mike5p0
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93' - MAC 2.5" off-road h-pipe w/ 2-chamber Mac's, 3.73s, Eiback sport springs, adjustables, screwy interior
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