where is the EFI located

You can't be pouring fuel into the carburetor because it doesn't have one, you must be pouring it directly into the throttle body and as that is unrestricted the engine will flair up the rpms until it runs out of fuel. The EFI system is located under the air plenum chamber, if you work on this yourself be very careful as by now the tubes are going to be very brittle, if you break one there is no fixing it, they will need replaced. You need to verify correct fuel pressure and flow first. Then check for power to the injector system, fuses first then onto wiring.