[02sequoialimited]

Hello, made a previous post back in August about my 02' sequoia about a ticking noise + glittery oil as well as CEL. Fast forward CEL was resolved with replacing a bank 2 02 Sensor and has been pretty flawless since. No misfires no CEL, runs smooth but ticking noise from cylinder 7 remains as well as slight oil consumption. Sitting at 183K miles, I was wondering if it is a good idea to up the oil viscosity to perhaps a 5W-40? I know somewhere in this motor there is metal on metal contact seen from the glitter in the oil and it will let loose eventually but in the meantime perhaps upping the viscosity to a 5W-40 will maybe be a help? Ticking is especially heard on startup then slowly lessens as oil circulates. I will also include a picture of a fried ignition coil from Cylinder 7 that ultimately led to this mess. Still have yet to figure out how this happened, maybe a stuck open injector or flat out coil failure, no one can figure it out. Thanks!

 

[Old Mechanic]

My guess would be the coil was not "well connected" to the plug and arcing which makes for a lot of heat and excess resistance from same heat. like an arc welder. Pop had a bad ignition switch on his mid 80's Ford and it would not shut off. I pulled the coil wire with insulated pliers and that damn coil arced more than 6 inches until I got it a good ways from any ground. All that unintended resistance got it hot enough to basically melt, leaving what you see there.
Makes you wonder if the plug was not the right one and left the gap since other than not being fully inserted in the tube and connected to the plug, it left that way when the plugs were last replaced, which should have been many miles ago.

 

[remember5]

I have 248,000 on my LR3 with a 4.4 V8 and I run that Castrol High Mileage Synthetic 5W-30 which is the viscosity recommended by the factory. At startup I want the 5 to circulate to everything quickly yet stay thin enough to circulate when its warm to clean sludge and the Castrol has some chemicals to help prevent wear and nurture the seals. It also has less phosphorous so it's easier on the cats. I'm still running the original cats and have done no major internal engine work yet. My Sequoia has it's oil changed at the dealer and only has 25k but I plan on using the Castrol synthetic when I start changing it's oil myself but plan on using the recommended viscosity. When I first started driving oil viscosity was not a big deal but I think manufacturing tolerances are so much tighter now that whatever they recommend is what you should use. Castrol GTX High Mileage

 

[scoutyjones2]

My guess would be the coil was not "well connected" to the plug and arcing which makes for a lot of heat and excess resistance from same heat. like an arc welder. Pop had a bad ignition switch on his mid 80's Ford and it would not shut off. I pulled the coil wire with insulated pliers and that damn coil arced more than 6 inches until I got it a good ways from any ground. All that unintended resistance got it hot enough to basically melt, leaving what you see there.
Makes you wonder if the plug was not the right one and left the gap since other than not being fully inserted in the tube and connected to the plug, it left that way when the plugs were last replaced, which should have been many miles ago.

Wouldn't it throw a code?

 

[PizzaAngel66]

Wouldn't it throw a code?

I am not very experienced in these types of things so if my comment seems stupid then I fully condone you ignoring it. I don't think it would throw a code so long as it was sending the spark/electric current at the right time. I would think that the smell would be the first tell.