[Riptidepro]

Hi everyone! This is my first post on Drive Accord and I'm glad I found this community.

I recently changed out my spark plugs on my 2014 Honda Accord Sport 2.4L at 140,000km (85k miles). I replaced them with new NGK spark plugs, however, when I removed the old plug I noticed that the ceramic near the bottom of the plug appeared burnt and there was some light browning above the burn marks. Also, under the hood I noticed a slight ticking noise that went away when I switched to the new plugs. The tips of the spark plugs look decent judging from other photos that I've seen online.

I was wondering if this is normal to have these kinds of burn marks and if these plugs could've gone any longer. Thanks and I'm happy to be onboard Drive Accord

 

[UnknownJinX]

You are fine. It's called corona stain and is a normal phenomenon.

PLUG STUDIO / NGK.

Sent from GM1917, technology or something like that.

 

[rlitman]

You are fine. It's called corona stain and is a normal phenomenon.

PLUG STUDIO / NGK.

Sent from GM1917, technology or something like that.

It is also a sign that you need to replace the rubber seals.

 

[t-rd]

You don't need to replace the spark plug tube seals on the valve cover gasket. There is no oil leak evidence around the plugs.

 

[rlitman]

You don't need to replace the spark plug tube seals on the valve cover gasket. There is no oil leak evidence around the plugs.

Not the plug we’ll tube seals. Those only need replacement if there is a sign of oil. So, you don’t need to take your valve cover off for just this.

No, I’m talking about the coil boots. The factory coils are probably fine, but corona is a sign of plasma leaking past their rubber seals, and the boots are designed to be replaceable (my replacement kit came with new springs too). Out of the factory, my COP seals were attached with dielectric RTV in strategic places, so I chose to replace that too, after a thorough cleaning.

Finally, make sure your plugs are immaculately clean, and then use a very thin coating of dielectric grease on them before installation.

 

[t-rd]

Not the plug we’ll tube seals. Those only need replacement if there is a sign of oil. So, you don’t need to take your valve cover off for just this.

No, I’m talking about the coil boots. The factory coils are probably fine, but corona is a sign of plasma leaking past their rubber seals, and the boots are designed to be replaceable (my replacement kit came with new springs too). Out of the factory, my COP seals were attached with dielectric RTV in strategic places, so I chose to replace that too, after a thorough cleaning.

Finally, make sure your plugs are immaculately clean, and then use a very thin coating of dielectric grease on them before installation.

Please post what you are talking about. Corona stain is normal and is the byproduct of oil vapor and electrostatic electricity. I've replaced over 30 sets of spark plugs across more than 8 different cars and they all have corona stain. You can clearly see on his plugs where the boot coverage ends, between the boot coverage and the plug where the exposed section is where the stain is. It is fine.

Straight from NGK:

Global Networks｜NGKスパークプラグ/NTKテクニカルセラミックス製品サイト

NGKスパークプラグ／NTKテクニカルセラミックス製品サイトの「Global Networks」ページです。

www.ngk-sparkplugs.jp

I don't see the coil boot as a separate part for purchase.

Plug Hole Coil - Plug (L4) for 2014 Honda Accord | OEM Parts Online

www.hondapartsnetwork.com

 

[rlitman]

I’m not saying that corona staining is necessarily a bad sign, but too much of it can be. What I mean is that the corona stain will be present at the service interval of these high energy spark systems. However, failing to clean it up may lead to the next set of plugs not lasting as long as the factory ones. Of course, considering the incredible first change interval, perhaps expecting that sort of life a second time may just be unreasonable regardless.

You’re absolutely right about what the corona stain is. However, it is also slightly conductive in a place that you need an ideal insulator. The stain on the plugs is water under the bridge, since the plugs are being replaced. But what’s left behind on the rubber is not so good.

Anyway, here’s what I used when I did my plugs:

2013 HONDA ACCORD 2.4L L4 Spark Plug / Ignition Coil Boot | Shop Now at RockAuto

Ignition Parts and More for Your 2013 HONDA ACCORD at Reliably Low Prices. Fast Online Catalog. DIY-Easy. Your Choice of Quality. Full Manufacturer Warranty.

www.rockauto.com