Breaking Ground Straps?

Broken ground straps on spark plugs….what causes it?

I’ve been seeing this issue pop up more and more lately, and I thought it was something worth discussing. The theory I am going to discuss is exactly that. My theory; on why some spark plugs straps break, and some do not. Some of you may have other theories, and I am all ears!

The first thing I do want to mention before my theory is that a lot of “NGK” spark plugs being sold online are not actually genuine NGK products. For this reason, NGK has put certification wrappers on all their plugs, to prove they are a genuine product. I always make sure that my plugs have these wrappers on them in all of my personal vehicles.

Now, when it comes to gapping, this is where my theory comes into play. Almost all plugs that fit into the Ecoboost engine are going to come gapped around .044-.046 (unless you buy them from a third-party vendor that is pre-gapping them for you). So this .044 gap will need to be closed up quite significantly. About .016-.020 if I’m being more precise. That is a pretty large drop, causing the material on the backside of the strap/weld to weaken. Now, if you go too far in your gapping attempt, and have to open the gap back up again, now you have also weakened the other side of the strap/weld, making it much more likely to fall off during combustion.

So to remedy/avoid this, you always want to go very slowly and only close the gap until the desired gap is reached. Avoid opening the gap back up at all costs! I have gapped so many plugs over the past 10 years, that I can pretty much do them without a feeler gauge, Lol. What I am getting at is that I never have to open the gap back up, and I can vouch that I have never had a strap break on me. So that’s something right? What do you guys think? Am I totally off here, or could I be on to something?