I have a 2008 Honda Civic LX 4 door automatic transmission with 98,000 miles. I picked up 4 NGK IZFR6K-11S 5266 Laser Iridium Spark Plugs. I bought them from RockAuto.com since they seemed to have the cheapest price with shipping. I also saw some super cheap ones on Ebay, but I don't want to risk them being fake (fingers crossed mine aren't fake ha). Anyway, I picked up some feeler gauges today (the one with the bent metal blades, NOT the coin style) and these spark plugs all seem to be pre gapped around .040. At what size should they be gapped for my car? I read .043, and some give a range. I've watched youtube videos showing that there should be a little drag when you slide the gauge in, but I'm trying to be careful to not break the iridium tip. Any tips and help is appreciated, thanks!

 

To be honest, I just usually throw them in and run it. I was told current plugs are usually pre-gapped to the application they are for. Even if that's not 100% accurate, .040 to .043 isn't much difference and I believe the car will still run on the .040 just fine. Over time the gap will widen anyway with wear and for awhile it will be ideal at the .043 until it's starts to go even wider. Even then the car will run fine for some time before needing to be changed out.

I too don't like gapping the tiny tip iridium plugs due to breakage and expense of the plugs.