Bought a 2001 honda civic about a week ago, put a new battery in it. It had very low idle, around 800. Driving at city speeds and suddenly the tachometer dropped to 0 and shortly after the car stalled. I was able to start it again and get it off the road, but the tachometer doesn't go above 0 when I start it, and it sounds like it's about to stall again. Any suggestions?