1988 Ford Bronco dumping to much fuel

. Really sounds like ecm failure.A you need to scan and check inj pulse width. The injector only stays open as long as the driver tells it too. Another possibility. Check the tfi module. And do a ohms test on injectors. Check and see if they are equal or if resistance is more in one injector. This is a complicated prob bear with me and check these things . Billymac