[san berny]

I changed the spark plugs and it started acting like it wants to down shift but then it doesnt, its like a transmission glitch. so I put the old plugs back on and it continues to do it. sometimes it feels like it changes gears to fast then the rpms are to low then it cant down shift. instead it jerks about 3 or 4 times then i either just give it more gas to force it in to down shifting or just lay off the gas for a second and drive slower so that it stops jerking. Any body know what this is?

[DodgyAnt]

I'm not sure what this is, but I think to find out more, you need the model number.

What is the model number, mileage, date of buying?