1999 Ford Windstar mileage: 108,000. Fairly frequent ping while under mild to moderate acceleration between 1300 and 2200 Rpms. The Ford dealership has done several adjustments in accordance to Ford Tech Service bulletins. I have tried mid and premium grade gas. All changes have made no improvement. From the questions posted, this seems to be a common problem with a lot of newer vehicles. Suggestions/Recommendations? Besides, trading for a different vehicle? Thanks.
Some Ford engines are not equipped with knock sensors. Yours may be one of them. Located in the wiring loom, close to the ECM, is a "jumper" that when removed retards the timing 4 degrees. This should correct your pinging problem.