I have a 2002 Montero and went to the dealer the other day to check about a heat shield that came off. In doing that, I mentioned that my gas mileage wasn't very good on my last road trip. The dealer said that at 75k miles, Mitsubishi recommends that the injectors be cleaned. I asked how much that was going to run and they said about 2 hours of labor - so I assume that they are running some kind of additive through the fuel to clean the injectors since 2 hours isn't enough time to actually remove and clean them.

Has anyone ever had this done or know what they use? Does it help? I have heard good things about seafoam, but I am kind of skeptical about how much an additive really helps the problem.

While seafoam will do some injector cleaning, I'd hold out til I find somebody to sell you some BG Products BG44K injector cleaner, unless you have the skills to pull the injectors yourself and have them ultrasound cleaned and leak/flow tested, which is by far the preferred method.

I also note that injector cleaning on the truck is a fat profit margin item for a service shop....

What was your MPG? What do you usually get?

well, the incident that I told them about was a 3 hour drive I had taken that weekend down the interstate where I got about 11 mpg. However, on the way back, I got 17 mpg. I used to get about 19-20 mpg on the interstate.

We use a Motorvac machine at our shop. you hook it up to the fuel lines and it runs off the additive rather than the tank fuel. not sure what they are selling you but this machine also cleans the valves to some extent as well as the combustion chamber. We charge $150 CDN here. I'd probably start with the basics though. Tire pressures, tune up. O2 sensors also affect fuel economy. It is a decent service IMO.
Mark