Having alternator problems?

My battery was going dead, and I had it checked and was told it was the alternator. I bought a new one, received a jump so i could take it to be repaired, and the engine began revving up and down real fast and then died out. It had never fone this before. It is a 2002 Ford Escort.

Have the sensors checked, to see if any of them was affected by the jump. Sometimes, to much voltage can be sent into the wrong areas, and cause things to malfunction. Cars are much more sensitive to voltage changes then they were fifty years ago. The TPS throttle position sensor uses voltage from about half a volt to over 4 volts, as it opens and closes the throttle valve. IF this is messed up, the computer might be seeing a swing in voltage, telling it to rev up and down. Other sensors might also cause this problem.

But even a vacuum leak could cause it, if a vacuum hose came off or something. Best thing to do, is have it checked by a shop, which had testers that can test sensors and other things.

When I say vacuum, a leak can cause AIR to enter the system, and so the oxygen sensor will then sense the high Oxygen in the exhaust and cause the computer to back down the engine, but then it will rev up again, and keep swinging.

So check out the sensors. And vacuum leak.