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Threads too wet, not normal. Spark plugs under torqued? Maybe oil leaking past the rings due to carbon build up? Maybe an oil leak from some place else into that particular cylinder. Just speculating.
For your 1st two pics, the the single spark plug and the 1st spark plug in the 2nd pic looks fouled. All others, not so much...but then again only 14,000 miles. I've had spark plugs come out @ 100,000 miles look cleaner. I would investigate further.
I bought them off eBay from authorize Lexus dealer the reason I replaced them I got misfire in cylinder 1 & 6 and car shake/vibrate badly on any stop and gets worse when I put AC on and rpm needle is dancing to the bottom but not to the top, and car is hesitate when accelerate on high speed, are spark plugs has anything to do with fuel induction service I did like 6 month ago and someone told after doing this service you should change spark plugs other wise you will have fouled spark plugs !!!
When a plug has carbon usually means that bank is rich, maybe the cause of your misfire is from a stuck injector or bad spray pattern. Do you have any engine codes? These cars have 12 injectors, 6 DI and 6 regular. I dont know to much about the direct injectors, but the regular injectors you can remove them and send them to a local fuel injector cleaners, where they will take all 6 injectors and manually spray them inside clear measuring tubes that allows you to determine the volume of fuel and the spray pattern. I would also buy oem o-rings top and bottom.
Or another option, run your fuel tank low on fuel and run a fuel cleaner. I did this with liqui moly fuel cleaner, I poured in 2 cans on an empty fuel tank and I tried my best not rev the engine too hard. My engine was smoother, after my fill up, and it saved me a few mpgs. Try this, and rexamine the plug cylinder that had the bad carbon on it, if it doesnt go away then pull the injectors and test them. If you find one or two bad injectors and the shop was unable to clean them out or revive them. Then you can replace just the bad ones with oem or denso brand. No need to replace all 6 injectors!
When a plug has carbon usually means that bank is rich, maybe the cause of your misfire is from a stuck injector or bad spray pattern. Do you have any engine codes? These cars have 12 injectors, 6 DI and 6 regular. I dont know to much about the direct injectors, but the regular injectors you can remove them and send them to a local fuel injector cleaners, where they will take all 6 injectors and manually spray them inside clear measuring tubes that allows you to determine the volume of fuel and the spray pattern. I would also buy oem o-rings top and bottom.
Or another option, run your fuel tank low on fuel and run a fuel cleaner. I did this with liqui moly fuel cleaner, I poured in 2 cans on an empty fuel tank and I tried my best not rev the engine too hard. My engine was smoother, after my fill up, and it saved me a few mpgs. Try this, and rexamine the plug cylinder that had the bad carbon on it, if it doesnt go away then pull the injectors and test them. If you find one or two bad injectors and the shop was unable to clean them out or revive them. Then you can replace just the bad ones with oem or denso brand. No need to replace all 6 injectors!
After 2 days of spark plugs replacement and driving the car for very short trip car was drive very smooth then today I got engine light on along with VSC light as well and I kinda hear pinging and ticking noise from the engine never really heard it before, so Rechecked All my work again and pulled up all the plugs to make sure if I maybe over tighten them or something one of the plug was burnt in cylinder 1 and it looks different than the rest of them and, so I went to autozone to see whats the code it came out code p0441 which EGR vacuum solenoid ,, which says replace evaporative emissions vacuum switching valve ? I called the dealer to see how much is it wasn’t that expensive like $100 but the part rep. Told me to check all my vacuum hoses and make sure everything is plugged correctly and the surprise was one of the vacuum line was unplugged not sure it got disconnect by accident or not but later I took the car for a test drive car still shake/vibrate when I stop, do ECM need to be reset so it can learn the new numbers, or should I disconnect the battery and see how’s everything or should I go and buy the VSV switch ??? Any help would be appreciated 🙌🏼
oh, pardon me, i guess your internet article by olivia marsh carries more weight than the 3 years i spent in trade school learning from lifelong techs, or the lexus factory training we revieved at the dealership lol
oh, pardon me, i guess your internet article by olivia marsh carries more weight than the 3 years i spent in trade school learning from lifelong techs, or the lexus factory training we revieved at the dealership lol
In your 3 years of training, they didnt teach you a carbon soot spark plug is a sign of a rich fuel mixture?
In your 3 years of training, they didnt teach you a carbon soot spark plug is a sign of a rich fuel mixture?
#1, they're not really teaching people how to read plugs out of ladas anymore. You're talking about an electronically fuel injected car that has a wideband afr sensor. It won't run rich without throwing a code. It honestly would be difficult af to get the car to run rich period. Lean maybe but not rich.
#2, rich mixture on a modern car would clean the plug. Would definitely not leave wet oil on it as the OP describes.
#3, what op described and posted is not carbon soot anyway. There's definitely carbon in it, but not the loose black dusty kind that would come from the impossible scenario you seem to think is taking place.
#4, I hope you're appreciating this free education because I would normally just ignore you by now.
#5, one of the users above rightly commented that they don't see much unusual about OPs plugs. Honestly sometimes they come out looking like ***. These cars run a ton of advance if you drive them like a grandma and most of us do. You can get some pretty ****ty looking plugs out of a any lexus these days, let alone any modern car with high compression.
#6 some of these engines do suffer from blow by. Its a pretty common issue.
#1, they're not really teaching people how to read plugs out of ladas anymore. You're talking about an electronically fuel injected car that has a wideband afr sensor. It won't run rich without throwing a code. It honestly would be difficult af to get the car to run rich period. Lean maybe but not rich.
#2, rich mixture on a modern car would clean the plug. Would definitely not leave wet oil on it as the OP describes.
#3, what op described and posted is not carbon soot anyway. There's definitely carbon in it, but not the loose black dusty kind that would come from the impossible scenario you seem to think is taking place.
#4, I hope you're appreciating this free education because I would normally just ignore you by now.
#5, one of the users above rightly commented that they don't see much unusual about OPs plugs. Honestly sometimes they come out looking like ***. These cars run a ton of advance if you drive them like a grandma and most of us do. You can get some pretty ****ty looking plugs out of a any lexus these days, let alone any modern car with high compression.
#6 some of these engines do suffer from blow by. Its a pretty common issue.
Im not going to reply with bashful hatred, I honestly wish you the best.
But if you think the scan tool will tell you everything wrong about an engine then sadly you will make a bad technician. These are parts slapper techs! They read a code, and right away fire the parts canon. Many dealerships hire parts slappers, thats how they make there money. If you want to become a good mechanic then you need to learn to read spark plugs, learn how to properly use peco scopes, learn to use thermometers, stethoscopes etc.
As for having soot or carbon on 1 or 2 sparkplugs and having those banks run rich is very common to not see it on a scan tool. When you say an afr sensor, your only getting a reading of all the cylinders in the down pipes from the o2 sensor and not at each individual exhaust port like you would with egt probes mounted on each exhaust cylinder runner.
Soot or carbon on a spark plug can easily come from a loose valve guide, valve seat, worn rings, scoured cylinder walls, or even through a bad emissions components. Once you get a little oil on the tip of the plug, that can easily foul a plug or reduce its performance and create misfires.
