Looking for some advise, I bought a 175 Johnson and owner told me that he got the check engine light occasionally I get it as soon as I start boat hasn't made it in the water yet. I try running the boat on my portable tank to ensure that it is not the boats tank and I still get it. I understand that the check engine light means a fuel restriction; filter on front of engine is clean, portable tank still get it. Could it be the vacuum switch, bad gauge , fuel pump? Any help is appreciated.