Possible COUNTERFEIT DENSO "U Groove" sparkplug KJ16CR-L11? Bought from authorized dealer, Advance Auto Parts

[Snowflake White]

I just bought a set of four DENSO spark plugs from an authorized Denso dealer (Advance Auto Parts brick and mortar store)
KJ16CR-L11 supposedly has a "u groove" ground on it. I checked this plugs and noticed that the ground instead has
a standard ground with a tapered end point like you'll see on a number of typical plugs today but clearly the u groove is not there I checked all the plugs.
Interestingly I checked some official authorized dealers and I have found pictures of the plug with the same tapered ground on them.
On the metal body it says DENSO JAPAN and plant code JD.

I wonder if Denso changed production on these or they are really counterfeit, box was sealed when I got it from the B&M store so hard to believe
that they were switched somehow.

Any help would be appreciated thanks.

 

[Jethro_Bob]

I wouldn't surprise me if someone bought from both Advance auto and Ebay and then took the Ebay plugs to Advance after tuning up their car. No different than returning used oil to Walmart.

 

[MolaKule]

Here is what the Denso product page shows:

https://www.densoproducts.com/denso-3132-kj16cr-l11-nickel-spark-plug

 

[slacktide_bitog]

email Denso and show them pics

 

[Snowflake White]

Yes I just wrote them an e mail asking about it. Seems strange to me. Odd part is that some of the pics I found from authorized dealers have the same ground pictured on them.

 

[Snowflake White]

Yes I just wrote them an e mail asking about it. Seems strange to me. Odd part is that some of the pics I found from authorized dealers have the same ground pictured on them.

I went to the official DENSO link page that MolaKule posted and the ground does appear to be the same on that sample picture,
however my plug does NOT have "CG" as a code on it, but instead "JD" is that a legit plant code?

 

[ARCOgraphite]

That is a pretty hot plug what is it going into? Old carbed low comp wedge OHV engine ?

 

[Snowflake White]

That is a pretty hot plug what is it going into? Old carbed low comp wedge OHV engine ?

Nope. 1994 Honda Accord 2.2L SOHC 4 cyl. The plug is the OEM factory installed plug.

 

[Snowflake White]

Just received a reply from DENSO itself and the rep said with the details I gave him he thinks the plugs are genuine, the ground spec'd for this specific application calls for a standard tapered ground not the U groove, and the plant code is correct too.

 

[mk378]

The U groove types seem to almost always have "U" in the model number.

My 1994 Civic has always had NGK V-Powers. I think Honda approves either for the OEM plug.

At the end of the day it's a $2.79 base metal spark plug. No one is going to bother to counterfeit them.

 

[Snowflake White]

The U groove types seem to almost always have "U" in the model number.

My 1994 Civic has always had NGK V-Powers. I think Honda approves either for the OEM plug.

At the end of the day it's a $2.79 base metal spark plug. No one is going to bother to counterfeit them.

True, and that's what confused me, why anyone would counterfeit a cheap basic plug...
Turns out the ground electrode can vary depending on which version of the plug is specified
the 4 pack box and individual boxes all specify "U groove" as a feature, but in tiny small print
on the back of the box it says "Contents may vary"

Actually the plug is specifically specified in the original owners manual from Honda, and it was what was installed at the factory when new.
NGK plug is second choice in the manual and is ZFR5F-11.

I just like DENSO because they are a major tier one and have been for Honda and Toyota since those companies started way back.

 

[slacktide_bitog]

I just like DENSO because they are a major tier one and have been for Honda and Toyota since those companies started way back.

So is NGK

 

[Snowflake White]

So is NGK

True. Denso is more wide ranging and has more resources, are they "better" maybe not but they seem to be more wide reaching than NGK.

 

[ARCOgraphite]

So is NGK

NGK V power have been garbage and their Steel plug GND wear out excessively fast vs. an ND or Champion.
And they tend to run a half step hotter than others. I would run Autolite before V power. And have with good result.

NGK OEM Ir plugs on the other hand have been excellent. The biggest ignition advance since distributorless ignition.

That K16/ Z5 is still a hot plug, IMO More for cold start emissions than good power and running.
But it all depend on how wide the operating HR is on the plug design. If it was my machine I d be trying a K20. But if it runs well
no need to try something different.

 

[nthach]

Any Denso plug with U in its part number is a U-groove part. Like K16R-U, W20EXR-U for example. Their Iridium Power plugs might also have a U-groove ground strap.

It’s kinda hard finding Denso plugs outside of a Toyota dealer. I’ve ran them with success on a Nissan and Honda small engine.

 

[mattwithcats]

I have been running one heat range colder in my Saturn...

ZFR5F-11 -> ZFR6F-11

https://www.rockauto.com/en/parts/ngk,4291,spark+plug,7212

 

[Britdude74]

I wouldn't surprise me if someone bought from both Advance auto and Ebay and then took the Ebay plugs to Advance after tuning up their car. No different than returning used oil to Walmart.

Rarely happed at my store but we were liberal at defecting parts

 

[zrxkawboy]

I consider Denso and NGK to be interchangeable. Many Japanese bikes will list both brands/numbers in the manual.

 

[billt460]

I went to the official DENSO link page that MolaKule posted and the ground does appear to be the same on that sample picture,
however my plug does NOT have "CG" as a code on it, but instead "JD" is that a legit plant code?

Don't put a lot of faith into these "code numbers" and manufacturing "I.D.'s" to identify parts as counterfeit. Companies change these things, or outright eliminate them all the time, for a variety of reasons.

I went through this a while back with a case of Toyota, (Denso), oil filters, that I purchased from an OEM parts supply group. I came across a bunch of links that supposedly showed you how to spot "counterfeit" Toyota oil filters, by missing various "codes" and numbers that only "genuine" Toyota filters have.

It was a bunch of crap. According to several of these links, my filters showed signs of being counterfeit, but they weren't. Yes, there are counterfeit parts out there, no question. But a LOT of these supposed manufacturing numbers and codes, are not accurate. As far as offering actual proof that they are counterfeit.

 

[HangFire]

I consider Denso and NGK to be interchangeable. Many Japanese bikes will list both brands/numbers in the manual.

I've noticed that too on my Honda motorcycles, and where both are listed, never hesitated to use either one. No problems, either.

Some time ago I had a back injury and I had my mechanic put in "OEM" spark plugs in a Honda J35 while he was doing the valve service. I asked for OEM thinking he'd get NGK, he put in Denso Double Platinums instead. I never blinked, and neither did the engine, it ran just fine.

As for NGK V-Powers, I've been running them for many years in my 3.9L Dakota. While the Dak forums are ruled by the COPPER CORE ONLY CHANGE THEM EVERY 12K crowd, I've never had any problems with the NGK's, even right before the heads were replaced with serious oil burning (the "magnum" heads commonly crack in the very thin spot between the intake and exhaust valves, then the valves shift slightly and the seals leak oil like crazy... but they keep running).