i just had the same problem with my 94 z28. had the same issues til the other day it died and wouldnt start, had to tow it the whole nine yards. needless to say i wasnt happy..haha come to find out it was all because i had corrosion on the coil..cleaned that and replaced the wire. started right up and perfect idle. i replaced the M.A.F as well due to chuggin/dieing issues.