I tried editing my original post and i accidentally deleted it. sorry for all you guys who read my post but didnt understand what the problem was. Here is the original post. I will try to edit the other posts I made so the thread makes sense. I have a 2008 Mercury 60 hp EFI Bigfoot. It starts fine, but won't run above 1,800 rpm. Engine dies down, but often doesn't stall, at WOT. It will slowly return to 1,800 rpm but runs with a throaty sound. I have changed spark plugs and leads, used Sea Foam spray in air intake, checked water separator filter, inspected low pressure fuel lines, used pressure gauge and clear tubing to check low pressure mechanical fuel pump for pressure and lift and to see if air was getting in the lines, removed and inspected high pressure fuel lines and filter, checked pressure at VST, removed and cleaned fuel injectors and fuel distribution manifold twice, and checked resistance on just about every sensor. My latest clue is that on two separate occasions I removed the high pressure fuel lines and filter, drained the fuel from the lines into a bucket, and noticed that the fuel looked cloudy. Cloudy fuel was also dripping from the fuel distribution manifold where the fuel line was connected. This cloudiness went away after a while, so I am thinking tiny air bubbles/foam? Don't know what would cause this though. After putting the fuel lines and filter back, the motor started at high rpm and sounded great, but then quickly went back to sounding the way it always does and not exceeding 1,800 rpm. This happened both times I removed the high pressure lines. I was suspecting the VST, so I checked that out today. Inside the VST looked good. The float and pump were clean too. After putting everything back together again the engin started up perfectly, but then died back down and wouldn't go above 1,800 rpm. that makes 3 times it has done that. Any advice anyone has would be greatly appreciated. I am stumped.
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