My 92 Grand Marquis which otherwise runs/drives fine, seems to be having issues at stoplights. It'll start to idle rough, the battery light will flash a bit, then it'll stop running. Also, it sometimes seems to be having trouble accelerating between about 60km/h and 80km/h. Any ideas? I know it's had its fuel pump replaced with an inline fuel pump, and it's not at every stoplight although it's more often now than before.