Starting prob
 

Hi guys, I have a 2004 4.4 x5 and I notice that sometimes when I turn the ignition to the on position the truck won't start but as i am returning key to off position it will fire up. At first I thought it was the battery (still has original battery 75, 000 miles) but after changing the battery it still did it. Original battery still good so I put it back in the truck. Any ideas plzzz . Thanks. And yes I did a search

Sound`s like it might be a faulty ignition barrel also have you checked the ignition fuse ?
I have seen fuses with residue on the pins and fuses worked now and again, clean fuse(s) with sand paper it might help?