I'm new to boating so I am grateful for this forum. I have a 94 La brisa with the 5.8L fuel injected Ford engine. It runs great up until 3000 rpm and then it sputters. The rpm's drop by 500, and the engine has no power. And it sounds sour. I have searched this site for similar problems, but to no avail. Has this happened to anyone else? Any help is thoroughly appreciated.