while driving my xj she starts to "buck" it goes from no power to normal power back and forth so much so i thought my transmission went out but it seems like its shifting with no trouble and now most of the time it seems to me that she does not have the same power as she used to i have been reading up and it seems like it might be the tps but you folks are geniuses and thought you could help (auto trans, I6 4.0l, brand new k&n air filter)

 

sorry have to ask....Plugs,wires,cap,rotor???

 

could be everything, need more detailed information.

 

My 86 xj had a loose ground on the motor that would pull loose when I pressed the gas, it would act that way, bucking around and such, but when I would let off it would go back to normal. Took forever to figure out what the problem was. Check all your grounds in the engine bay.

 

new plugs and wires i didnt change the rotor or the cap and it only does the bucking about 5% of the time