Misfiring of engine
A misfire is typically the result of a fuel, spark, valve, or intake issue. Misfires are sometimes difficult to diagnose until tests are done to collect data. Fuel pressure, compression, and vacuum tests to name a few would be where I would start.
Check engine light on? If so have codes read. If in USA most auto parts stores will do for free. Post numbers back on here so we can better help you
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