Talking to a friend about an issue he is having with his 175hp Mercury EFI. He needs to give it a little throttle when he starts it to get it to run, and it will idle a little rough. When on plane it runs great, just the start up and idle concerns. The mechanic has gone over it twice and said everything looks great and just turned up the idle a little bit.

 

Kind of stumped at what this may be, anyone got some ideas or similiar experiences with the same issue.

I see that you are in Maryland. If this problem is new this year, I would always start with the easiest solution. 1) Bad Gas, 2) spark plugs need to be replaced, 3) fuel filter..etc. In my experience the new ethanol gas tends to be the culprit for these types of problems more times than not. Throw some octane boost and some additive to remove water from your gas and replace the plugs and filter- then see if the problem improves.

Injectors clean? 

I suggest adding SeaFoam to new gas and run it again............Al