This is my first post. I have read all the rough idle posts and still have a question. I have a 2002 90HP 2-stroke Mecury Outboard that runs smooth after 2,300 RPM, but misses, smokes, idles rough to beat the band at idle and at trolling speeds. I have had it to one repair shop who cleaned the carbs, ran sea-foam through it, cleaned the gas tank dry and refilled it with marine grade gas, it was worse when they gave it back and charged $630. I then contacted the factory and they suggested an authorized dealer who again, cleaned the carborator and installed new jets, plugs and tuneed up the motor and gave it back after billing $423. So now I have about $1,000 in trying to get this Mercury to run smooth so I can troll and idle. Any more "expert help" and I might as well get a new 4-cyl 4-stroke (which runs great on my other boat. Can anyone tell me any advice on what I can do other than use this motor as a boat anchor? That is where I am at with this Mercury. A dealer said that if I went with an E-Tec I would not now be having this problem, but I have another Merc and it runs very smooth and I have had a 90 HP Johnson that ran smooth for 25 years. And this Merc ran great when new. Can anyone help me with this. I have tried cleaning, jets, water removal, lline and tank cleaning, new plugs and wires, sea foam, carbarator cleaning sprays, mechancial carborator cleaing by the dealer, etc. etc. It still runs like a bucking mule.
