"I disagree with fsskier."
Actually, we do not disagree!! Techron was recommended by GM in the beginning in both service bulletins and in printed publications, when injector clogging was suspected. This was, of course before the upgrades to gasoline detergent levels.
This takes Techron out of the "mouse milk" additive category and into something that may be used (once a year perhaps) as part of your maintenance program. Any others using the same chemicals should also be ok.
I would not recommend putting it in for every road trip though.
Incidentally, my TBI injector on the 3.1 litre APV is easily visible and still works well after 275 k miles - and I have never added anything to the gas. This is in no way to say that some vehicles might not have buildup - our Audi did - but it was a 76 and ran 10 years of the pre-injector detergent gasolines. And yes, it did clean up, only running the new stuff, and two bottles of Techron!!
OK, the Audi story: At high miles, it began to start on 3 cylinders and run on 3 until partly warmed up, then picked up the 4th. The dealer said "yup, we see it all the time" the injectors get buildup on them and the gas just dribbles in. As the engine warms up it vaporizes well and starts running ok. Their recommended repairs - new injectors - was quite high priced, and by then the Audi had become my daughters college car.
Its about a mile to the interstate from our house, the 4th cylinder was kicking in about the time she got onto the interstate - the problem had gotten worse for the last year.
Added the Techron, and the "kick in point" started moving about 200 feet closer to home every morning, after one tank of gas it would work within a block of our house.
By the end of the second tank- and second bottle of Techron- it would start on all 4 right from the beginning. The problem never returned - although we never added more Techron, the oil companies were rapidly upgrading their gasolines.
Suprisingly, the gas mileage did not go down much during the fail mode, apparently the dribbled but vaporized gas was burning well - after the first mile each day, of course.
Likewise the power was a constant also when running on all four.
Sorry to make such a long post, but to make "an anecdote" have any sort of evidence takes details. And of course my first post was general advice against adding unknown chemicals to your car. I still would not recommend any for regular use.