I have an 06 360 4x4 I bought new. It ran fine till I took it to the dealer for maintenance after a few hours. After that it tends to stall when I let off the gas. I had the valves adjusted and it ran good again. Now it has gotten worse than ever. It will only idle if the choke is partially on, stalls every time I let off the gas, is hard to start, runs rough and backfires.
I can't do the maintenance myself, had the valve clearance checked, replaced the plug. No one seems to be able to find the problem. Has anyone had this problem? and what can I do about it?

TIA

 

Check/measure valve clearance again and let me know what they are.

 

Sorry for not doing this sooner, I forgot about the post.
Turns out the problem was a crack in the carb holder. Was under the clamp so you couldn't see it without removing it.
I appreciate the responses

 

Is that the black rubber boot that holds the carb to the cylinder head?

 

Yes, that is the part. Couldn't see it till you took it apart because it was under the clamp.