Originally Posted by cleric670

Definitely not making the right decision. There is no code that says "improper plugs", if you have code P0300 which is the multiple misfire then you should start by removing and inspecting all the plugs and coil packs. You might just have one not torqued down properly or you might find damage on the coil pack like a melted boot or something.

If the plugs look worn then replace them with stock NGK plugs, I strongly recommend the stock NGK PLFR5A-11

If you have any other spark code like P0301, 0302, 0303, 0304, 0305, or 0306 then that's for a specific cylinder that's misfiring.

Buying all new coil packs is a waste of money, you might have one or two damaged coils but they typically last a VERY long time and aren't exactly a wearable item.

If you have oil saturation in the spark plug well that's probably why it's misfiring, the spark plug well tube seals are a common failure point and when it fills up about 1" with oil it starts to misfire. Replacing the valve covers if that's the problem.

Troubleshoot! Don't just throw parts at a car hoping something fixes the issue, it's expensive and time consuming.

Here is a link to the factory service manual, spark plugs are in MA - Maintenance, if the well tubes are leaking oil the valve cover replacement is covered in section EM - Engine Mechanical under "rocker cover".

https://www.nicoclub.com/infiniti-service-manuals