Yes, I am confident that they are good. I never had any issues with cylinder 2,4,6 which these were on. I had the same CEL codes a couple of days ago before I switched the coil packs. So, whether I use the old ones or the new ones, I get the same codes intermittently on cylinders 1,3,5. The one constant code I get is the P171. If the spark plugs were the issue, I wouldn't get a lean code, would I? Do you think all of the back spark plugs could have an issue at the same time? BTW, the car has 145,000 miles on it so I know that the spark plugs are due for a replacement. I just can't understand how the codes are for 1,3,5 all at the same time???
I also want to thank you for you help, I really do appreciate it.