98 GT pinging

[Technick]

At 60K I would suggest a fuel injection cleaning, preferably by a Motorvac, made by Sun and usually sold by Snap-on. Not something you just go out and buy. Cost is $4,500.00 So a repair shop is the only place that will have one. Cost can be from $90.00 to $150.00 I owned one once when I ran my own performance Mustang shop. There is NOTHING better (outside new fuel injectors) at cleaning fuel injectors, cleaning carbon off of the pistons and valves as a Motorvac. PERIOD!! I have seen this machine cut the vehicle emissions in half! It has solved many a driveability issue. It is not the end all, cure all. But it does work. The Snap-On man let me use one for 6 weedks for free just so I could see for myself how good the machine was. It was everything he said it was, so I bought one. Still wish I had it. Not an easy decision to buy considering it's cost. But it was worth it. Having the injectors clean can go a long way to having a great running engine. Just be sure to change the fuel filter at the same time.
Oh, and do not forget the "other" tune up stuff that should be done at 60K also.