98 ford windstar keeps stalling

this happens about once a week.
heres the kicker, it only stalls from a stop while making a right turn.
I'm sure this is a coincidence, but everytime it has happened, its during a
right turn from a stop sign.
If you drop it into neutral to restart it, it won't.
you have to completely stop the van, put it in park..and then it will start
right up like nothing was ever wrong.
any ideas?


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