Venice 49cc 2008?

Engine starts but won't accelerate and adle speed slowly goes down until it dies. Will restart with same thing. Got the muffler off now and feels like it weighs but 8lbs. Is that about right or is it getting plugged. Had carb. off and cleaned but didn't see anything wrong. There is a solenoid attached to metering rod on carb., not sure how it's supposed to work. Any info would be helpful. Thanks.