Yesterday my car started idling very rough on the way into work. I decided to wait try and just take it back home after work and figure out what was going on. When I left the office, it was still idling very rough and white some was pouring out of the exhaust. This continued to come and go and I only made it about a mile and decided I wasn't going to be able to make it home. Is there anything else it could be? Its a1995 FJ80 w/ 337000 miles.