Code E-38 is vaporizor malfunction,generally when this code shows the Vaporizor needs rebuilt,is cheaper to rebuild a NIKKI vaprizor than it is to replace it with a new one is just a handful of diaphrams and a "flapper valve" assembly Tar rots the diaphrams and they rupture and cause over pressure if it is to bad then it gets to the injector and injector holder assembly,in that case will need to take apart and clean the injector holder and injector or just replace the injector and be safe with it.