safe mode has several causes and the only way to find out if it is a fuel issue (generally a non detectable issue by the EMM sensors like fuel restictions) is to connect a PC (cheap basic PC with windows 10 and USB ports) and check the active fault codes stored in the EMM.
as a ETEC owner it is highly suggested that you acquire this " tool" .
Some basic versions like V5.0 can be downloaded free from the ETEC user board but a smal triangular cable is needed to link up to the EMM so you may as well buy new from on line suppliers ($$) or a dealer ($$$$) . It is the modern aspect of servicing these CPU driven outboards.
here is a write up on EV DIAGNOSTICS. Dealer service is fine but asmall investment may save you money in the long run.... up to you ! btw if you do get shop work insist for a PDF copy of the full report from your dealer. it is a simple request and you paid for it. it will also provide injector coefficients info for future needs,
EVINRUDE DIAGNOSTICS VERSION 5 A GUIDE TO GETTING STARTED September 2021 INTRODUCTION This guide is primarily intended to help Evinrude E-TEC owners. The words...
docs.google.com
FYI here is one report from my own 75hp as an example