Hi, I have an au Fairmont and I had it sitting for about a month... the battery went flat so I disconnected it and charged it but now whenever I stop or even slow sometimes it isles very low and sometimes stalls also loss of power steeringAny ideas of what this could be... also had the drive belt replaced recently but havnt had any issues until now

If it wasn't doing it before you left it to sit I would say the fuel may have gone bad or you may need to reset ecu. Get in your car turn the key to on put foot on accelerator all the way to the floor and your other foot on the brake. Now wait for over 2 minutes but less than 3 so about 2 mind 30. Once time has passed both feet off the pedals turn the key to off remove it if unsure then go for a drive. I was told this trick from an ecu specialist and I've done it and I've gotten close to 40km extra out of a tank full.