I bought a 2004 ranger professional series 1500 (one of the yellow ones). It has the 650cc vtwin engine, FYI. Ever since I got it new, it never idled right. Unless you slowly let your foot off the gas, it just stalls, unless youve been using it for hours on end. Also, whenever you decelerate from anything above 3/4 throttle to a stop, it backfires quite loudly. the dealer looked at it twice, once saying the plugs fouled, which did nothing. So, I tried a different dealer, which replaced all the clutch buttons and sheaves, claiming the trans wasnt shifting causing it to not idle, which also did nothing. I really think its a carb issue. The plugs always look fine, not burnt or black, ive tried adjusting the idle speed, but it really does nothing, and it is always serviced. please help, I kinda getting fed up after dealing with this for almost 4 years now.

 

It definantly sounds like a fuel problem to me. When my rhino was having a problem becouse I had some silicone stuck in my intake tube to my fuel pump it was running lean and when I let off it would backfire real loud. But if I ran it wide open for about a minute or two it would cut out at top speed and start sputtering. If yours doesn't do that I would look at your pilot jet becouse yours dies when it tries to go down to an idle and is backfiring you might be running lean becouse your pilot jet or the pilot jet orafice is plugged up. Hope this helps you.