I am a true believer of fuel injection cleaner and for the sluggishness of your vehicle, I believe a bottle of STP Complete Fuel Injection System Cleaner or better yet a can of BG44K will do the trick. The solvent will clean the fuel lines, valves and combustin chamber from having carbon deposits. For every 15,000 milies, I routinely clean the combustion chamber with BG Fuel Systerm Cleaner via the vacuum line of after-the-throttle-plate method, and pour a can of BG 44k (or substitute with two consecutive tankfuls of gasoline with two bottles of STP Complete Fuel Injection System Cleaner). The result is much smoother ride and better gasoline milieage. Currently with city/highway driving, the mileage is about 21 per gallon. Highway driving would yield about 28 per gallon.

You may not want to wait till another 15,000 miles. The Techron Fuel Cleaner available at Costco can be used every 1000 miles in your fuel tank. Or you can use BG44K or STP Complete Fuel System Cleaner now, and see if the sluggishness would go away.

I bet it would make a big difference in how you car drives.