1998 Johnson Ficht 175 water in fuel alarm

[whalerbob]

Late last season my the alarm on my outboard starting going off and the engine light would come on. Evinrude diagnostics says it is water in the fuel. I have drained the fuel twice and I have never seen any evidence of water, the water separator is new, I replaced the fuel line and bulb from the water separator to to the engine, I have removed the lower engine cowling and did a visual inspection of all the fuel lines. It's important to note the problem is intermittent. This is probably not related but I will throw it out there anyway, I had the boat running for about 10 minutes without the fuel cap on, I put the fuel cap on and the alarm went off almost immediately. I took the cap off and restarted her and the alarm went off again. Anyone have any ideas where to check next?

 

[Faztbullet]

Code 37 was a common problem false code on 1998-99 models..only fix is to have EMM updated. Don't have any idea why cap does this other than vent clogged.

 

[whalerbob]

When I took my water filter off earlier today it was only half full, shouldn't this thing be full after running? Do you have a easy way of checking to see if the vent is clogged? A clogged vent would possibly explain the alarm after putting on the fuel cap.

 

[whalerbob]

So I checked the sensor wire for continuity and it checked just fine. I ran the engine and the alarm and light came on, I disconnected the wire to the sensor and started the engine and the alarm came on. Is it safe to assume it's the ECU?

 

[Faztbullet]

yep

 

[whalerbob]

I got the ECU back yesterday from the computer guy and the problem appears to be eliminated, no alarm and no engine light. Thanks