Denso spark plug authenticity check

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Bought 6 plugs for a Lexus V6. PITA to finally take out the rear 3 plugs. Now I want to install new Denso plugs, which came in a 4pack and 2 individual packs. All gapped around the same and iridium tips look same colour and laser welds on all 6. The only thing I noticed is the DENSO word is a lighter shade on the 2 individual pack which is the left 2 in the following photo. On the hex, one is printed 2EM for 4pack and ENK on 2 pack. Rest of words and packaging are all the same. Is it just 2 different batch that cause this variance in printing? [Linked Image from i.ibb.co] image uploader
 
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FWIW, I do not order OEM parts from Amazon. The last 6 pack of Euro Castrol 0W-30 I ordered from Amazon looked different from the norm. I'll probably dump it in my recycle drum. For my BMWs I use Pelican, Turner, or an online BMW dealer. For our Honda and VW I only order from online dealerships. Scott
 
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Originally Posted by SLO_Town
FWIW, I do not order OEM parts from Amazon. The last 6 pack of Euro Castrol 0W-30 I ordered from Amazon looked different from the norm. I'll probably dump it in my recycle drum. For my BMWs I use Pelican, Turner, or an online BMW dealer. For our Honda and VW I only order from online dealerships. Scott
Same here. I'll buy a lot of car parts from Amazon, but not plugs and anything that I'd rather have 'OEM' for. For those I'll do Rockauto, Brick and Mortar, or an online Honda/Acura dealer.
 
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The uneven pale blue lettering on the left two is a hallmark of counterfeits. The hex flats used to be stamped (not lasered) with a 4-digit lot code.
 
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Originally Posted by SLO_Town
FWIW, I do not order OEM parts from Amazon. The last 6 pack of Euro Castrol 0W-30 I ordered from Amazon looked different from the norm. I'll probably dump it in my recycle drum. For my BMWs I use Pelican, Turner, or an online BMW dealer. For our Honda and VW I only order from online dealerships. Scott
The problem with Amazon is they mix their stock and FBA stock in the warehouse and it all gets picked from the same place so it allows for supply chain contamination.
 

wing0

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I bought them like 5-6+ yrs ago and I just can't find where I got them from. I'll put the 2 odd ones on the front bank so easier to change them if they are fake. All were gapped to 0.44 and have blue tint on the electrode tip
 
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I would be curious to see a pic of the business end of them if you don't mind before you install them. There are usually tell-tale signs there as well. Wish I had paid attention to mine. I just put 6 Denso's in my Accord. I didn't even bother to check the gap on them or really look that closely. They came from Rockauto.
 
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Originally Posted by ctechbob
I would be curious to see a pic of the business end of them if you don't mind before you install them. There are usually tell-tale signs there as well. Wish I had paid attention to mine. I just put 6 Denso's in my Accord. I didn't even bother to check the gap on them or really look that closely. They came from Rockauto.
Rock Auto should be fine, their stuff should be coming straight from the manufacturer, unlike say Amazon where even if you buy from Amazon, they mix 3rd party's stock to be fulfilled by Amazon with Amazon's regular stock in the warehouse and you might get fakes if a third party seller sent counterfeit inventory to Amazon..
 
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Originally Posted by blufeb95
Originally Posted by ctechbob
I would be curious to see a pic of the business end of them if you don't mind before you install them. There are usually tell-tale signs there as well. Wish I had paid attention to mine. I just put 6 Denso's in my Accord. I didn't even bother to check the gap on them or really look that closely. They came from Rockauto.
Rock Auto should be fine, their stuff should be coming straight from the manufacturer, unlike say Amazon where even if you buy from Amazon, they mix 3rd party's stock to be fulfilled by Amazon with Amazon's regular stock in the warehouse and you might get fakes if a third party seller sent counterfeit inventory to Amazon..
That came out wrong. I totally trust them to ship the real stuff. I'm just curious now what the printing and stamping looked like on the 6 I got. I think my old NGK's are still in the trash can though. I might have a look at those just to compare them to NGK's online counterfeit avoidance page (They were bought from RA too)
 
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I wouldn't buy plugs on Amazon. Maybe E-bay if the seller was a dealer parts dept. Recently bought plugs from my local Subaru dealer even though they weren't the cheapest. Counterfeit plugs seem to be a problem.
 
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Honestly the fakes are almost impossible to distinguish from real ones now, they are that good. I bought some plugs for my inlaws car and stared at them with the OE plug out of the car and they matched perfectly. I bought "OE Nissan boxed plugs" as I was afraid of fakes in Denso boxes. Guess I did not keep up with times as they also fake OE plugs now as well. 10k later they were worn out to a nub and misfiring. I generally order from rockauto now. Never got a fake from them and great prices. Just watch out for the "new" NGK and Denso single iridium plugs. They are NOT rated for 100k+ life. Amazon I believe stopped mixing inventory so they should be safe as long as its Sold and shipped by them. The autolite and new Bosch Iridums at advance with coupon are also good if you need them right away.
 
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I'm not bashing Rock Auto and I'm not bashing Amazon. I'm not comfortable buying auto parts from either. I won't buy plugs from either of them. I don't even go to the autoparts stores. Really paranoid, I know. I only buy plugs from the dealer. Most plugs in my cars are good for 100K-120K. To answer your question, I highly suspect you got at least 2 fake Denso plugs. Just return them and get your money back. Now, there is one other option to consider. IF you can verify an Amazon seller is a dealership that would probably be ok. Just call the seller and confirm they are a legit dealer.
 
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Originally Posted by blufeb95
[ Rock Auto should be fine, their stuff should be coming straight from the manufacturer, unlike say Amazon where even if you buy from Amazon, they mix 3rd party's stock to be fulfilled by Amazon with Amazon's regular stock in the warehouse and you might get fakes if a third party seller sent counterfeit inventory to Amazon..
I didn't know Rock Auto shipped direct from the manufacturer. I thought they had this warehouse network system set up.
 
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Originally Posted by Jimzz
Honestly the fakes are almost impossible to distinguish from real ones now, they are that good.
The problem now is, companies like Denso, NGK, etc have pages on their websites showing what to look for when trying to determine if the plugs you have may be fake. Don't they realize, the counterfeiters can just use this information as a guideline on how to make better fakes !
 
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Originally Posted by hallstevenson
Originally Posted by Jimzz
Honestly the fakes are almost impossible to distinguish from real ones now, they are that good.
The problem now is, companies like Denso, NGK, etc have pages on their websites showing what to look for when trying to determine if the plugs you have may be fake. Don't they realize, the counterfeiters can just use this information as a guideline on how to make better fakes !
Good point. The best way to ensure getting the genuine article is to buy at a reputable outlet and check them before purchasing.
 
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