Worst Timing

[NV_D_XG]

Dont you just hate it when things go wrong on your car at some of the worst times? I was camping out at the murry for new years at strathmurton and on my way back from cobram, my alternator blows! Indicated by the battery light...and ALOT OF BLACK SMOKE. Finding someone who would replace it on new years eve wasnt very easy, by the time i found someone i didnt have a working speedo anymore. I eventually pulled in at Stokes workshop in cobram who fitted a new one for $280, and also rushed the job to the point i had to re-tension the belt. My question is, since ive replaced my alternator, it idols extremely low? to the point that if i try to creep in reverse then lay off it will stall....Do alternators cause this sort of problem? It also climbs revs a bit when i place it into Drive from park and then drops back to idol speed, and vice versa from Drive to park. I mucked around with about 4 different batteries and had it disconnected for about 1 hour prior to getting a new alternator, is the ecu ****ed off?