Spark plugs - 2007 Lexus ES 350

I’ll check with the oem, i do replace the plenum gasket. I’ve got 260k miles on this and i want to drive it till it stops working. The spark comes were changed 6 months ago, though this time i didn’t use oem. I figure if i go to the parts store and read the code it will be another spark plug. I was wondering if it was a device sending the voltage erraticly.