Hello I will help you with your question,
You have the 4 cylinder 2.4L engine correct?
The Ignition failure sensor is on top of the engine and is responsible for telling the computer that the coils did fire the spark plugs. It also sends the signal for your engine speed to the tachometer on the instrument cluster. This sensor is failing and you need to have it replaced.
I am not sure why the dealer had no clue but that is not unusual. The sensor can leave you stranded so it needs to be replaced.
You should be able to have the sensor replaced for about $150
Please let me know how I can help you with this
is this a defect or something that just normally has to be replaced?
They do wear out over time just as any electronic device that is heated, frozen, vibrated and subjected to shocks will. After 10 years you have to expect some things to need to be replaced.
Please let m e know how I can help