Noisy fuel pumps which suddenly aren't noisy any more are usually dead ones. However it doesn't usually trigger a check engine light if my memory is correct. Check engine lights/no throttle have been known to be dodgy ECU's.
The best thing to do is plumb in a pressure gauge to the RH rear corner of the engine, where the fuel temperature sensor is located (take out the temp sensor and screw in an appropriate adaptor). This should read 58psi with the ignition on, if it doesn't then the pump is probably knackered. If the pump is producing the right pressure, then I'd try a new ECU next, but you need a computer to program the security code and injector grades which could be a problem in the middle of Africa...