I suppose that I wasn't clear regarding my objective in using a fuel system additive.
I just did a valve job so the valves are clean and the compression is as new. I'm not trying to use a fuel additive to get the added zillion horsepower as might be claimed in a J.C. Whitney ad.
I'm also not trying to up the octane. I thoroughly understand the effects of octane increase and decrease.
My objective is to ensure that the injection system flow is not inhibited. In the Dallas, Houston and probably a few other Texas cities, it was mandated a few years ago that they sell "reformulated" gasoline. This has additional additives to keep engines clean, thus in theory, keeping the engines running more efficiently, thus decreasing air pollution. In East Texas where I live this fuel is not mandated.
I have begun since I began this thread to use Texaco CleanSystem3 and Chevron Techron Premium from pumps in Richardson (Dallas area) rather than buying an additive chemical.
In my original question, I was seeking inforamtion regarding an additive that I might use to "blitz" the system, before beginning the diet of "reformulated" fuel for a while.
Power is off some in my 300E, and the engine is by no means worn out as suggested earlier in this thread. The engine has the compression of a new engine. Either the injection system or other engine management components are not working exactly right, or maybe the ignition is not being advanced properly by it's control mechanism. Since there are no mechanical advance mechanimisms, I don't know exactly how to check it. I do plan to at least put a timing light on it, and ensure that the ignition is advancing.
Additionally, when putting the engine back together, I regapped the plugs that came out of the spoiled engine and stuck them back in. I now have a new set of plugs and a fresh fuel filter that I plan to put in while on vacation next week.
Thanks for your responses,
'01 C Class, Six Speed
'84 Euro 240D, manual, 533K miles
'88 300E 5 Speed
'81 300D Daughter's Car
Over 800,000 miles in