Well it is not the cap.
It sounds like something electrical, does the fuel pump run when you switch on(prime).
If it does not hot wire it and see if it then is ok, if it is then you are missing fuel pump feed.
If this is ok then you need to look for a spark, no spark could be the coil on the way out(gone).
You really need to ascertain if you are misssing SPARK or FUEL, then get back.
tabetha