1986 mustang gt set for a long time floods on idle and misses and jerks bad at about 1and 1/2 on rpm on tach now installed new sparkplugs stil does it and uses excesive amount of gas
Check the timing, and for vacuum leaks. You can also try scanning the car for codes. You need an OBDi code reader or a paper clip...http://www.muscularmustangs.com/test1.php
Check out the rest of your fuel system. If it sat for a long time and had gas in it the car probably has clogged carb jets or injectors if it is a fuel injected car. A good fuel system cleaning is probably in order to get the car running right.
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