before my vx threw the belt, i was looking at different instrument "snakes" , and rifle cleaning brushes, just for the purpose we are talking about, cleaning that tube......if its the same one im thinking about, you can see the end of it in the throat of the trottle body. 7.62 seemed a little too tight, and i didnt go real deep at all. plus i think there is a bend or two in there, so thats why i was thinking about an trumpet or french horn snake. these snakes are like a tightly wound spring, thats kinda stiff, but will go thru tubing and corners and such, and they have a stiff NYLON brush on each end. the whole snake thing is about 3 feet long. feed thru the throttle body, come out at the egr? my idea was cut short, and still have the stuff, but not the vx to work on.
i had also been using sea foam deep creep spray down that tube, as it breaks up carbon making it easy to scrub away, but i dont know how well a nylon brush would hold up with the spray. if it would melt the plastic, also why i was looking at the rifle bore brushes.
sitting here thinking aobut this, i wonder, if after soaking the tube in deep creep, and letting it soak for a bit.....if the "right brush" could be tied to a light, yet strong string, then, feeding that string into the tube in the trottle body. attach a shop vac at the egr, suck the string thru the tube, and out the egr, shut off vac, and pull the brush up thru the tubing, and repeat. dont know, wish i could try that one out. sigh

well, ill quit rambiling, but i know that tube is always dirty on mine, and when i clean my egr, i always cleaned that tube best that i could,but i never felt like it was the best cleaning that could be done.............