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Q: Cylinder #6 misfire on 4.0 liter SOHC

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I've replaced EGR plugs wires TPS idle control valve coil MAF sensor still show #6 misfire starts and runs but had vibration at 55 mph do u have an idea what this could be and has been wrong with similar vehicles cost to fix? Thanks Dan.

My car has 212000 miles.
My car has an automatic transmission.

Hello. Good job on getting the basic tune-up work done! Given the mileage, this engine may have a longer-term issue, namely, accumulated wear on piston rings or a blown head gasket. Both of these can be diagnosed with a compression test, or a leak-down test if compression numbers are more consistent than engine running suggests. If the miss is constant and regular, a burned valve is also a good possibility. I recommend having a professional, such as one from YourMechanic, inspect the misfiring issue in person to diagnose this problem and assist with repairs.

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