Not to scare you but those could be im saying could be symptons of a head gasket/cracked head problem. How does the oil cap look? You losing coolant?

My 2010 ranger at 200k miles was having those symptons when boom white smoke and misfiring.

It had a cracked head and an engine rebuilder shop fixed it. 2 years later after it was fixed it wants more and more.

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2010 2.3 Stick Reg Cab XL - Maxtrac 2 inch coils - Bilstein 5100 front shocks - Bilstein yellow rear shocks