I have a 1999 Cherokee that recently started acting funny. I'll be driving, when all at once the gauges start going crazy and there's a big jerking sensation..like the engine wants to quit. Someone suggested it could be the alternator? Any suggestions would be appreciated. Thanks in advance.

 

could be your crank position sensor, could be a bad ground. Cheapest and easiest thing is check all your ground connections. Make sure they are clean and tight.