Yes i have a 99 bmw z3 coupe will not start been 2 the bmw dealer they replaced the computer but stil couldnt fix the problem, it started with i let car sit up for a month covered , went too go start it was dead tried jumping it with a jumpbox no go my truck no go ended up replacing the battery then it turns over but wil not start smoke arises from the hood where computer is a single brown wire is burned up going too a cluster of brown wires all tied together but only one of them burned up the computer a transister inside the computer fried think it went too the fuel pump not shear.but i have the car back at home now ned help you can spray starter fluid and it will start but i dont know what is keeping it from starting please help.

Fuel is not getting to the engine. It is no longer an electricial problem unless the fuel pump is not working, if it is an electric fuel pump with I am fairly sure tha it is.If it sat that long. Did it run after they changed the computer? Could be that water has condensed out of the fuel.
Disconnect the fuel line . have someone turn it over to see if pump runs while you capture a small cup ful of gasoline. If fuel pumps out . fuel pump is working. 
Look into the gasoline in the cup and see if it has water in the bottom of it?This is where I woudl start.   Fuel is not getting to the engine. It is no longer an electricial problem unless the fuel pump is not working, if it is an electric fuel pump with I am fairly sure tha it is.If it sat that long. Did it run after they changed the computer? Could be that water has condensed out of the fuel. Disconnect the fuel line . have someone turn it over to see if pump runs while you capture a small cup ful of gasoline. If fuel pumps out . fuel pump is working.  Look into the gasoline in the cup and see if it has water in the bottom of it?This is where I woudl start.