Hi all, I have a 2002 Grand Cherokee Laredo. I have been experincing a hesitation, almost bumpy, acceleration AND decelleration. The rpm show no change, and there is no stalling or cutting out. No loss of power at high speed. This happens when the car has been driving/is warmed up for at least 20 minutes, but not every time. Not extreme jolting, almost as if you were driving down an unevenly paved road. While this is happening, brakes are also affected, heavily pulsating as if I was stepping on and then letting off the brake. Suspecting the brake issue is a warped rotor, but interested why it is only this bad when the "bumpy" accel/deccel issue is happening. After about 5 minutes or less, issue stops and car runs as normal. May happen again a few minutes later, may not. This happens about every other time I drive it, in any weather, terrain, speed(except highway speed). This has been going on for 2 weeks, took it to my mechanic and he couldn't figure it out. A mystery to the mechanically inclined I know. Any thoughts/similar issues? I'll take suggestions - thank you!