I have a bronco 2 1988 2.9 driving at highway speed 75mph it misses a few times than drives normal whats the cause
It could be a slug of water in the gas. It could be a spark plug wire. It could be a cracked or dirty distributor. It could just be showing it's age. If it's something bad, it will start missing more and more and you can find it.
As Tenspeed mentioned, it could be a spark plug or distributor issue. I remember when my '88 B2 went from sounding like a healthy 6 cylinder to sounding like a Model-T. It was a bad spark plug that went while on the PA Turnpike.
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