Premature spark plug wear

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My Camry has been acting a little rough lately. I would feel a little "bump" at highway speeds when the rpms slowed down from 2000 rpm and the tranny upshifted and the rpms dropped to 1500. I mistakenly thought it was tranny related. Coming home last night it was having more issues so I thought it would be bad enough to store a pending code and it did and then the CEL light up on the dash. P0301 which is a misfire on cylinder 1. I flipped the coils from cylinder 1 to cylinder 2 and still had a P0301. This surprised me. I switched the spark plugs from cylinder 1 to cylinder 2 and put the coils back to the original orientation and got a P0302 misfire on cylinder 2. Hmm, bad plug which was surprising since I replaced the plugs 25k miles ago. On examination, the plug was not discolored but had a large gap. After I bought new plugs, I realize the old plugs do not looks good at all. I bought the old plugs from Amazon. I'm thinking they were counterfeits or defective Densos. What else could cause this? The car runs fine and I don't notice any change in gas mileage. The plug at top is the one that is causing misfires and throwing codes but the other ones don't look much better. A new plug at the bottom for comparison.
 

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They probably were counterfeit. Fakes have no durability. Never understood why people go the oem route for plugs. Ngk laser iridiums are more than good enough. A lot of oem's will buy those to slap their oem label on and sell for more anyway.
 
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That centre electrode should not be that eroded in 25 K. Hard to tell but that cyl looks like it was running hot also given teh stark white insulator nose. Was the plug loose? Was the plug tan on the other side of the nose?
Does you car have mechanical cam followers? Might have a tight EX valve. or a Leak on the IM near that runner.
 
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Leo99

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That centre electrod shold not be that eroded in 25 K. Hard to tell but that cyl looks like it was running hot also given teh stark white insulator nose. Was the plug loose? Was the pulg tan on the other side of the nose?
Does you car have mechanical cam followers? Might have a tight EX valve. or a Leak on the IM near that runner.
The other side of the plug is tan. When I put my reading glasses on and inspect there are a lot of issues with several plugs and chalk any issues up to the plugs themselves for right now. I'll dig deeper if any issues follow.
 
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The other side of the plug is tan. When I put my reading glasses on and inspect there are a lot of issues with several plugs and chalk any issues up to the plugs themselves for right now. I'll dig deeper if any issues follow.
I would bet on counterfeit and plain high nickel steel electrodes at best.
I recall pulling the factory IR plugs on my wife's Suzuki Vitara 2L 4 banger and they looked fine at 114K miles
 
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I bought what I thought were 'real' Denso plugs for my Rav4 a couple years ago from a seller on eBay that had 10's of thousands of positive ratings. Turned out they were fake and I started getting misfire codes after about 19,000 miles. Not fun doing plugs on a transverse V6. Bought genuine plugs from Napa.
 
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You can check the Denso website to verify those plugs. In the meantime get a new set from a reputable dealer.
 
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Likely fake - did amazon sell them or was it third part? I have not seen a fake from "shipped and sold by amazon" so I would be interested if its happened.

I would also check them again in 5000 miles or so. Its possible the plugs are fine but your cylinder is overheating due to pre-ignition or something. It will have the same affect, and you would want to know sooner than later if that happens to be the case.
 
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Toyota's are picky about plugs. Denso or NGK is what they run best with. Buy from a local retailer not on line. Some cars run fine with whatever you stuff in the hole but not Toyota's.

Paco
 
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Likely fake - did amazon sell them or was it third part? I have not seen a fake from "shipped and sold by amazon" so I would be interested if its happened.

Buying from Amazon is no guarantee of getting the real thing, as they co-mingle their own inventory with that of third-party FBA sellers :cautious:
 
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My Camry has been acting a little rough lately. I would feel a little "bump" at highway speeds when the rpms slowed down from 2000 rpm and the tranny upshifted and the rpms dropped to 1500. I mistakenly thought it was tranny related. Coming home last night it was having more issues so I thought it would be bad enough to store a pending code and it did and then the CEL light up on the dash. P0301 which is a misfire on cylinder 1. I flipped the coils from cylinder 1 to cylinder 2 and still had a P0301. This surprised me. I switched the spark plugs from cylinder 1 to cylinder 2 and put the coils back to the original orientation and got a P0302 misfire on cylinder 2. Hmm, bad plug which was surprising since I replaced the plugs 25k miles ago. On examination, the plug was not discolored but had a large gap. After I bought new plugs, I realize the old plugs do not looks good at all. I bought the old plugs from Amazon. I'm thinking they were counterfeits or defective Densos. What else could cause this? The car runs fine and I don't notice any change in gas mileage. The plug at top is the one that is causing misfires and throwing codes but the other ones don't look much better. A new plug at the bottom for comparison.
Total counterfeits......Amazon is full of them.
Full.
Those densos could go twice that and hold their gap.
 
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Buying from Amazon is no guarantee of getting the real thing, as they co-mingle their own inventory with that of third-party FBA sellers :cautious:
So I don't doubt you, but you have any details? Everything Amazon owned is spread around the warehouse. There is no big bin of denso plugs somewhere. There might be the same denso plugs scattered in bins across the entire warehouse. They might be in a bin with oreo cookies and socks, because the algorithm tells them that people order those 3 things together and the entire algorithm is about efficiency of picking parts. So if I order one from a 3rd party, is it picked from the nearest bin irrelevant of ownership, or is it picked from the bin based on its owner. I don't know - but I honestly don't think they co-mingle - for the simple reason that then they would be on the hook to handle the warranty or return for a defective 3rd party part.

Having rambled all that, amazon gets there crap from a wholesaler like everyone else, so I wouldn't be surprised if they get fakes, but I still would like to know in this case from the OP.
 
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