Q: I have a 2005 Lincoln navigator that the number 6 spark plug is misfiring on.

asked by on January 09, 2017

My car sp[uters when accelerating over 40 mph, after a min or so it feels like it clears out and you regain your power. I took it in to firestone and they told me my number 6 spark plug was misfiring causing it to sputter. They then told me it would cost 675 to correct?

My car has 119000 miles.
My car has an automatic transmission.

Engine is misfiring Inspection $94.99 - $114.99 Get a Quote

Hello. A misfire can be caused by a number of things. Depending on what they found to be the problem it is quite possible that this is an accurate estimate. Most of the time this is caused by a failure in the ignition coil, but it may need spark plugs also. In a lot of cases this can also be caused by a valve seat failure in the engine but that will typically cost much more to fix. From my experience with this vehicle I would suspect an ignition coil which should not cost this much. I would get a second opinion, like from YourMechanic, where a certified mechanic can come to you do [diagnose why the engine is misfiring] https://www.yourmechanic.com/services/engine-is-misfiring-inspection

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