I have a 98 2.7 liter, 5speed. For several months now I have had a symptom that I thought was water in the gas. At any given moment under load but often when you ease up for a moment and then give more throttle. The truck will cut out for a second. It could be a soft hiccup or a sharp jerk. Sometimes it comes in multiples. Never really stalls but it sometimes feels as though it might. I used alchohol and "HEET". Sometimes it seemed better, sometimes worse. Today I dropped my gas tank, emptied it and dried it and put in fresh gas. It still does it. Any clues?

85 4Runner 22re, mostly stock. Over 340K miles(SOLD for $4000 7/06)

98 2.7 4cyl 4Runner Bone Stock perfect 200,000 miles (alright, it has a HG and clutch in it's past)