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Q: Hesitation

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i have a 04 grand marquis question for you is would you happen to know why at a red light stopped the marquis hesitates/shakes and coughs and will go slowly up to speed and like jump almost when it gains full power and then it is fine it does not do it all the time but does it frequently also i have had all spark plugs changed as well as the ignition coils.check engine is on and the code thats read is ignition coil number two and ihave switched that coil again incase its defective coil but it still comes back on with computer reset..hope you can help thanks in advanced

My car has 167500 miles.

There are several possible causes for an engine misfire. Although the most common causes are a faulty spark plug or ignition coil, it is possible that there is a failing fuel injector, or internal engine damage, such as a bent or burnt valve. If it were me, I would suggest first double-checking to see that the plugs and coils are functioning properly, and then focus on the fuel injector for the cylinder in question. Once those are proven to be in good working order, I would start looking into the other possibilities. If this is something that you could use a hand in diagnosing and/or repairing, contact a certified mechanic, like those available at YourMechanic.com.

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