I have a 3 year old Troy Built mower with the Honda GCV190 auto choke/auto throttle. Last year (2nd year) it ran very poorly/erratic... but it ran/did the job. This year (3rd year) after cleaning air/carb/etc it will start, and it starts with a very solid/as new performance. The choke automatically turns off, and it seems the throttle control tries to open, which together seems to kill the engine. I wait a minute, set choke, and it cranks right up nicely, then choke off, throttle auto opens, and kills engine. Extremely frustrating. What might be causing this and how can I resolve the root cause? Welcome helpful suggestions. Thanks...