As part of my 90k mile service I added a can of Sea Foam to the car. I used the online directions of 1/3 a can in the throttle body, 1/3 a can in the oil sump, and 1/3 a can in the fuel tank.

The most entertaining part of the process is clearing the fluid from the throttle body. The fluid is poured down the warm throttle body and given five minutes to seep into the ductwork. The car is then ran until the fluid is evacuated, with the sludge, out the exhaust.

Not something you want to do when your neighbors are grilling outside.