Hoping to get a little help but I'm seeing high idle on a '15 6000 (600 ctec2). Upon initial start up, 2200-2500 rpm, but then when running it and coming to a stop 3500 rpm. throttle cable checks out, it has slack and is not tight. throttle body shuts all the way. Can't seem to find any air leaks with starting fluid. new reeds on last year. On occasion it does start kind of funny and backfire a bit. . Not a lot of these I can find where people with 600 ctec2 had high idle. I've seen where it could be the IAC, or maybe an injector. Any insight would be great as I'm kind of perplexed, thanks in advance. Just looking to solve without taking to a dealer as we don't have a dealer close by anymore.