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Q: Ignition coil and Check Engine Light issue - 2008 Mercury Mariner

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2008 Mercury Mariner. I had all of my sparks plugs replaced in Sept. and one ignition coil was coming up bad on a scan P0351. My mechanic moved the A coil to the B coil spot so that when it did go out that it would be easier to get to to replace. Sadly, he was injured in an accident and is in the hospital paralyzed. I have the new coil. Car is misfiring more. Can you tell me (show me) where the B spot is? I know I can replace it myself - watched enough videos- just don't know which one it is. Yes, I am female - HA! Thank you for any help.

My car has 108000 miles.
My car has an automatic transmission.

A: Hello, thanks for writing in! There is no s...

Hello, thanks for writing in! There is no such thing as a B location for a coil. You have six coils, that is one per cylinder you have. Without knowing where the bad coil was relocated to it would be hard to know. It will be one of the front three coils since the back three requires the intake manifold to be removed for access to the coils.

The Check Engine Light code P0351 relates to the PCM computer primary injector driver problem and burns out the coil driver for that coil.

The repair may require the replacement of all six coils and the engine control module (PCM). This problem is internal circuits of the PCM get burned out from the excessive coil resistance.

Once these components are replaced the PCM will need to be programmed to work with your key through the anti-thief module. The programming will need to be done by a Ford or Lincoln Mercury dealer.

To avoid any unnecessary repairs, I would highly suggest having a certified technician, such as one from YourMechanic, come diagnose your Check Engine Light firsthand and service your ignition coils as necessary.

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