Toyota Repair: 99 4Runner could be a lemon, 4runner sr5, gas situation


Question
I recently purchased a '99 4Runner sr5 v6 4x4 from a private seller.  75K miles.  On my first road trip after its purchase, going up into the mountains of northwestern VA, engine was stuttering any time I accelerated.  One time it was so bad that the engine made a couple of brief popping sounds and check engine light blinked for a bit, went off, then came back on, and then after about 5 miles, went back off again.  I carried it to a mechanic that weekend, did plugs and wires, and some additive to the gas.  Situation improved, a couple of tanks of gas later, but it is still sluggish on accelerating, especially after just starting it.  Seems almost like it is flooding out. . .  On a more recent trip, all highway driving, check engine light came on, and is on now, despite no strange behavior of the vehicle during the trip (meaning no more sluggish than usual).  I am a full time student, and need to have an idea of what's going on so the repair shop doesn't milk me for the last few bucks I have.  Please advise if I have a $15,000 lemon.

Answer
I need to know why the check engine light is on, I need to know the diagnostic trouble code before I can help, if there is an Autozone store near you take it there they can help you get the code at no charge, if not, you need to take it to a repair shop to get the trouble code, without this information I can not help.