Originally Posted by jzeiler
I don't see how having residual injector cleaner in your crankcase is a GOOD thing!?! I think I would want it out of there. Did I miss something?
Sorry for a very late reply, but I never went back to look after Christmas to see if the thread kept going.
Anyways, the following is a condensed version of a summary I got from a friend who designs fuel additives for a living and has been for a very long time:
There are two different basic products out there - an "all-in-one system cleaner" and a "fuel system cleaner." Generally the former is the silver bottle stuff and the latter the black bottle stuff, but there also is about a 2 to 1 price difference that sets them apart. The former includes a friction modifier, the latter does not.
Either product enters the crankcase around the rings (not EGR). For those of you that are sure you set your rings really tight on breakin....there is still enough room for heavy organic molecules to get by them.
A simple fuel system cleaner should be added one tank before the oil change, as was indicated above in this thread. The detergents from this product enter the crackcase and actually serve as detergent to wash it out in an oil change.
The all-in-one cleaner should be added after an oil change. The friction modifier hangs around in the oil and helps keep the piston action smoother. Improvements in both fuel economy and emissions have been document with use of this type of product.
Overdose testing with both products has shown that you have OD it by a huge factor to create a problem.
The bottom line was that using either product is of value. The all-in-one has more overall benefits, but it is somewhat a matter of preference.