My 2007 Nissan Altima (83K)recently developed a misfire complete with flashing check engine light. This lasted for approx. 4 weeks & before I could get it in the shop it suddenly rectified itself. Also, even though I double checked the size/type of replacement spark plugs, the very same socket (deep enough) that fit the new plug would not fit the factory installed plugs & I could not get 'em out! At it stands right now, I guess I didn’t need to replace them anyway but something is going on and I’m a bit mystified!
Have your plugs been in there for 83,000 miles? Find the correct size socket. At least take them out, look at them, measure the gap, and put anti-seize on the threads if you reinstall them.
Yes, these are the original platinum tipped plugs, and according to more than one mechanic could still be ok. However, what’s baffling is why my socket fits the new plug (3/8")but won’t go over the old plug. These are OEM NGK plugs.
I have 102,000 on my original plugs, but you don’t want them to stay stuck in there so anti-sieze the threads. Try metric if SAE doesn’t fit.
I tried the 16mm but it still wouldn’t go over the old plug. And there’s not that much clearance in the well.