I have a 2001 duramax, the engine was washed while running. Ran fine for about an hour, then started sputtering. Sounding like an old farm tractor. Then died. Could start it for a while. Through several codes, all having to do with injectors. Now the truck wont even start. Blew out the connectors for the FICM and used die electric grease in them. Still no luck. Please help.