IAC valve sticking

[white diamond]

Is there a fuel additive that will help prevent this or is removing and cleaning after so many hours the only option?

[aquamort]

Nope...fuel additive wont help at all for IAC valves. You can buy cleaners in pressure packs from most stores (its a bit like a thinners in a can) that you can spray into the intake if that doesnt do it remove intake boots etc and grab an old toothbrush and with the spray scrub the carbon away as best you can. What is it on?

[white diamond]

2004 DF250 about 1,200 hours