you may want to try this .....
more expensive than the techron route. have heard it is effective.
Re: bg44k[200/88] posted by Dave Stevens on
Tuesday, 31 July 2001, at 6:27 p.m.
BG44K is supposedly not a consumer product and is sold only to the trade. You can try getting it through a friendly shop or auto supplier or you can try getting it from one of the auto e-tailers. The prevailing wisdom seems to be that BG44K is an excellent, but very strong cleaner, really only appropriate for use on badly carboned/neglected engines, especially considering its cost. I mean, you don't need oven cleaner to do the dishes.
Other top end/injector cleaners you may want to try are AMSOIL PI (through distributors like our Paul S), Chevron Techron (concentrate) and Redline SI. That's more or less the order of preference I've seen. Some of the house branded injector cleaners (like GM and Mazda) are reportedly as strong as BG44K. There are many other injector cleaners out there, some may be okay, especially for routine use. Just be sure to avoid the cheaper, older solvent based cleaners that might attack the fuel system and injector seals.
Periodic use of additives (like every year or so) should be the most that's necessary if you use quality gas, your engine is properly tuned and you do a reasonable amount of highway driving. If you buy cheaper gas with minimal additives or lower octane than the engine requires or if you do strictly stop and go driving, then more frequent use (like every few months) may be required.
One of the simplest tune-ups for improving engine operation is a throttle body cleaning and a shiny new set of plugs followed by a long, high rpm drive through the mountains. I'm guessing the optimum engine speed for this is probably close to the max torque for your engine and under load. If you don't want speeding tickets, hey, just stay in a lower gear.