My cusion has complained that some times her '88 Camry DX with the 5S- FE and the four speed auto with 120,000 miles lags when accelerating. She said it only happens once and awhile under acceleration it will kind of pulse or jerk of sa few seconds before accelerating? The fuel filter in it has maybe 25,000 miles on it. The plugs are OK, I cleaned the throdle body about 12,000 miles ago?? The last time it happened she was nearing the end of a tank of gas that I had added fuel injection cleaner to. She mainly does around town but does do highway, once every two weeks or so.