About 30,000 miles ago, I put a new set of spark plugs in my 2002 LX. It had around 95k on odometer so I figured it was a good time to swap them out. From what I could tell, all were original. I purchased a set of eight from a seemingly reputable ebay seller who had lots of JDM & Toyota parts and no mass quantities of spark plugs, leading me to believe the purchase was legitimate.
Fast forward to this morning, I’m taking my wife to work and while on interstate at around 70mph, I get bad vibration and flashing check engine light. Knowing this is typically indicative of a misfire significant enough to cause damage to cat, I exit and limp to an Advance Auto to use their OBD reader & pull codes. Got two misfires, cylinders 2 and 7. I knew I had factory coils on 123k; I felt fairly confidant they were the culprit. After moving a few around, restarting, etc I still get misfire and rough idle on same cylinder with flashing check engine light. Hmmmmm
I decide to pull coils and check plugs, here is where it gets interesting- all seven of the plugs I purchased from eBay (I dropped one, bending the ground electrode so I knew cylinder 1 had a Denso from Advance in it, this was replaced at same time as others) had rounded or missing center electrodes. I don’t know how it ran as well as it did for as long as it did, gas mileage is always norm, +/- 13.5ish around town.
The Denso from advance was literally fine, I can only attribute the premature failure I experienced to counterfeit plugs. It’s simply too coincidental that all seven would look this way except the one plug I knew was legit. Just FYI- don’t save a few bucks and make sure you source plugs from reputable seller. Photos attached of two of the bad plugs (all look identical) as well as a shot of the lone good plug. Crazy stuff!
Fast forward to this morning, I’m taking my wife to work and while on interstate at around 70mph, I get bad vibration and flashing check engine light. Knowing this is typically indicative of a misfire significant enough to cause damage to cat, I exit and limp to an Advance Auto to use their OBD reader & pull codes. Got two misfires, cylinders 2 and 7. I knew I had factory coils on 123k; I felt fairly confidant they were the culprit. After moving a few around, restarting, etc I still get misfire and rough idle on same cylinder with flashing check engine light. Hmmmmm
I decide to pull coils and check plugs, here is where it gets interesting- all seven of the plugs I purchased from eBay (I dropped one, bending the ground electrode so I knew cylinder 1 had a Denso from Advance in it, this was replaced at same time as others) had rounded or missing center electrodes. I don’t know how it ran as well as it did for as long as it did, gas mileage is always norm, +/- 13.5ish around town.
The Denso from advance was literally fine, I can only attribute the premature failure I experienced to counterfeit plugs. It’s simply too coincidental that all seven would look this way except the one plug I knew was legit. Just FYI- don’t save a few bucks and make sure you source plugs from reputable seller. Photos attached of two of the bad plugs (all look identical) as well as a shot of the lone good plug. Crazy stuff!
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