on 1998 olds regency alternator putting out 11.9 volts at idle. battery has been replaced , alternator checked good at 2 different auto supply stores. if revved up voltage at battery goes to 12.5 but right back down when throttle released . also abs and traction lights are on. any help would be appreciated.

How are the connections at the battery? Corrosion seems to be a factor.

i cleaned them, but will reclean at battery and also other en at alternator and other end of ground cable, will post results, thanks