Every week or two there’s a posting here about someone having their car in for scheduled 30K/60K/90K maintenence and being told the car should have some additional service done. The overwhelming response is that the customer do only what is outlined in the owner’s manual and nothing more. That seems especially true when it comes to fuel injection and intake cleaning.
I think it’s worthwhile to say that we (shops) know what we are doing and when I say your car should have a fuel injection and intake service every 30,000 miles it’s not padding the bill or selling snake oil. It’s keeping your car running normally.
This picture may not mean much to the average motorist, but to the people here who know what the inside of an engine should look like it may be interesting. There is obviously an abundance of carbon buildup and coking on the intake valves. If the customer had done the Induction and Fuel Injection service every 30K the intake and valves might not look like this at 86,000 miles.
Throwing a bottle of Techron in the tank certainly doesn’t hurt anything, but it does nothing to prevent a problem like this.