A while back someone had mentioned some other type of fuel system cleaner other than BG44K. If I remember correctly, it is some type of marine product. Something-Foam or of the like. I've been looking for it to use because I've used it before but now just can't remember what it is.

Got it at Napa, couln't find it anywhere else. But it did indeed help reduce the carbon buildup on the back of the intake valves (cleaned it totally off) after I went through 2 cans of it.

Search the web for more info on it, but lots of people reccommend slowly sucking it into the intake via vacuum line (pull one free), and spraying down the intake with the spray version.. basicly loading the intake up until the engine stalls. Then they let it sit for an hour or so (close it up so it won't evap as fast...) and start the engine. Most people floor it - everyone gets a nice smog effect!

I did something along those lines, and it did indeed remove the valve buildup. Hope the same thing works with the X... I have not tried it on an X yet.

-=RB