Small Engines (Lawn Mowers, etc.): Loss of power of gas trimmer, gas string trimmer, electronic module

Question
I have a 2-cycle gas string trimmer (Poulan/Weed Eater 1400T) that starts fine and works good until it warms up (3-5 mins). I just has no power when I rev it up. At first it cuts fine. It idles fine once the problem starts and doesn't want to die under load it just has no power.  This problem started late last season and I didn't work on it till this last weekend. I took it apart, cleaned the fuel filter, replaced the fuel line and the spark plug, put new gas in and had the same results. When I took it apart and went to clean the carb it looked fine. Not a speck of dirt or grime on it (good air filter (just a piece of foam)). I also ran it without the air filter to adjust the carb and had the same issue.
There is also a sealed electronic module that attachs to the spark plug. At this point I don't know if it is the carb, the electronic module, or something else. Any advice?
Thanks
Todd

Answer
It sounds like it just needs the carb adjusted.  Start by setting the mixture screws on the carb at 1 1/2 turns out from lightly seated.  Then you set the high speed by holding the trimmer at WOT and turn the screw in until the engine reaches maximum RPM and then open the screw 1/8" turn from there.  This should be sufficiently rich to provide adequate fuel under load.  The low speed needs to be set so that engine revs up from an idle with no bogs or hesitation.  If this doesn't correct the problem, write back with you found.  Hope this helps.