Ive uh.... had quite the experience with my ezgo marathon , but at this point i finally have the WOT and low speed AFR dialed in right .... here in "other vehicle's" ive posted an entire thread on it.
I dont know much your motor, but if its 2 stroke i can provide quite a bit of knowledge ive learned thru blood sweat and tears....
I feel like practically a 2 stroke gasser guru at this point because of all the diagnosing
If shes a 4 stroker, its a different story that im not on the up on, but 4 stroke is a subject we all at GMSB know.
Hows it getting fuel? I googled your model and added "fuel pump" at the end and it looked like it doesnt use crank case pressure to actuate it, but it does appear its likely got a diaphragm internally.
Make sure that isnt busted, it may regulate pressure like mine does.
The "idle" adjustment you speak of is a single screw on the side of the carb probably....
Its the low speed adjustment screw, probably has a spring behind it.
Read about adjusting those, but for my 2 stroke its all the way in, then 1.5-2 turns out
Too far out, itll just crank and and crank a while because its too much air, finally catches.
Too far in, and youll get lean pops or a backfire thru the carb whent the blades close
Think of it like a controlled vacuum leak like a IAC valve or your idle adjust ment on a carb.
Secondly, if its the oem carb and pump, at all costs dont throw them away, i regret throwing my oem pump away because the aftermarket components are crap.
They are sub standard and operate at a lower fuel pressure than the oem stuff, thus meaning..... less power.
I can help more but probably need more details.