New Sparks plugs and knocking..
I bought my truck, an '04 4.0 v6, with 80k on the odometer. From day one, the engine had always made this knocking/pinging that I had attributed to spark plugs. It only did it starting at 2500 rpm up a steep incline. I read in the owners manual that it is normal for these engines to have some knocking under load, so I just let it go at that. I changed my spark plugs the other day, and it made of world of difference, better mpg, smoother shifting etc. It feels like a new truck! However, the knocking is still there, only it has changed to about 2000 rpm and still only up big hills.
I replaced them with Autolite 5144, gapped to .54. The truck was still on the original plugs when I changed them, and the gap on these oem motorcraft was off the chart! ( as in it was so big my gap gauge couldn't read them)
So what would you guys do?? Change the plugs again? Maybe just regap them?? Or should I just accept the noise and live with it as I 've been doing? I really don't want to redo the plugs as it was a huge PIA, but....
I appreciate any input and experience ya'll can share with me.