very high fuel consumpsion,gas drips from exaust manifold when running,blue-whit

Hello, If scan tools are not able to transmit information to and from the ECU, plus the fuel mixture is so rich that you are fouling plugs... I have to say, this immediately makes me think the ECU has failed, or the connectors need to be cleaned, cleaned, and then cleaned again with electrical parts cleaner. Disconnect the battery first. If cleaning and inspecting the connectors and pins on the ECU does not correct the communications issue between the van and the scanner, it is time to start testing the ECU for proper voltage. What work has been performed? New or used parts?