I have a cylinder five misfire code. This is commonly fixed by replacing the coil for that cylinder and possibly the spark plug as well.
In most cases a misfire condition can be corrected by inspecting and replacing the spark plug and ignition coil for that cylinder. For your Ford Expedition, I would recommend replacing all of your spark plugs and ignition coils to be certain that your engine is running tip top. In some cases, a misfire can be the result of a bad fuel injector or camshaft timing being off due to a faulty variable valve timing solenoid. To be 100% certain this is it though, I would recommend enlisting the assistance of a certified mechanic, such as one from YourMechanic, to come by and diagnose your misfire condition to confirm the exact cause. They will also be able to assist with the repairs needed to eliminate the misfire and keep your Expedition running smooth.
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