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2006 Yamaha F90 Question?
I have a 2006 f90 I pruchased brand new. It has only 241 hours and recently had to replace the voltage regulator due to overcharging (17+ volts). I noticed for the past 6 months or so it has been getting harder to start after a long run up the river. I've changed spark plugs and fuel filters but nothing seemed to make a difference till recently. I drained the fuel tank and the vapor separtor tank (VST). I then added a can of sea foam with 89 octane fuel thinking this might help the starting issue. It actually seemed to help. Then about two weeks later my family and I were headed to our favorite fishing spot about three miles up the river and we were running along about 4500 rpms then it started ****ing and eventually died to about 1500 rpms. So we coasted back home at that speed. I put it on the YDS(Yamaha Diagnostic System) when we got home to find one code. A code 37 which it said intake air apssage, check that no air is leaking in intake passage. OK so i did to find nothing wrong there. Then I ran the test to fully open the ISC (idle speed control) valve and it failed and the motor died. This test has failed ever scince I started having this problem so now this is where Im confused. Did I mess up the high pressure fuel pump and filter assemly with the sea foam causing these problems or did the voltage regulator over charging cause a problem with the ISC valve? PLEASE give me your thoughts.
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