Question edited for clarity and fix funky punctuation and lack of spaces.
Question moved to model category.
My first thought was that the timing belt had snapped, but you have a timing chain and it says this
Does a Ford Windstar have a timing belt or chain?
Best Answer. Your Ford Windstar had two engine options and they both ran a timing chain, not a timing belt. Belts need to be replaced at around 100K miles, but since you have a hardened steel timing chain, you have nothing to worry about. Your chain should last the life of the engine without being serviced.
May 28, 2019
Has the oil ever been changed. You saying there was a 'pop' concerns me but it may have been a backfire, or unburned fuel popping through the Throttle Body.
And then there is the grinding sound, but that might just be the starter on the flywheel.
The only way to diagnose is to call out a mobile mechanic.
https://www.google.com/search?q=mobile+mechanic+near+me
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