I know the service manual says replace the spark plugs at 60K, but has anyone let them go longer than that?
KA4993
Changing plugs at 60k miles is much too soon for iridium plugs; 60k would be about right for platinum plugs, which were the long distance champs before iridium appeared.
I love doin them, its all a matter of budget and if customer is particular about the factory maintanence of their car. I've always let the customer know in advance when their vehicle unless its an older tacoma hits 100k to be ready for spark plug replacement and the cost associated with it. they're soo easy to do. I charge the least labor time in the shop here. I never try to sell plugs untill 120k again unless its an oldere tacoma with the 4.0 then they get them every 30k miles.
From the 2015 Highlander maintenance manual:
120,000 miles or 144 months Check installation of driver’s floor mat Inspect and adjust all fluid levels Inspect wiper blades Re-torque propeller shaft bolt (4WD) Replace cabin air filter Replace engine air filter Replace engine oil and oil filter 1 Replace spark plugs 4 Rotate tires
There is no requirement at 60,000 miles on the 2015 Highlander.
120,000 miles or 144 months Check installation of driver’s floor mat Inspect and adjust all fluid levels Inspect wiper blades Re-torque propeller shaft bolt (4WD) Replace cabin air filter Replace engine air filter Replace engine oil and oil filter 1 Replace spark plugs 4 Rotate tires
There is no requirement at 60,000 miles on the 2015 Highlander.
I just ordered 6 from the offical toyota parts site. When you input your zip code, the nearest dealership will show up along with its price. Go down the list of dealership because each dealership has different prices.
I found one, the 3rd nearest to me, selling plugs for $12.55/each. Use coupon code FREESHIP to get free shipping.
You're guaranteed to get genuine parts and it's cheaper than rockauto because it's free shipping and no tax!
I found one, the 3rd nearest to me, selling plugs for $12.55/each. Use coupon code FREESHIP to get free shipping.
You're guaranteed to get genuine parts and it's cheaper than rockauto because it's free shipping and no tax!
2017-2019 Highlander has direct injection so they get fouled up a lot quicker as a result of the direct spray vs port injected gas. I just bought 6 from AutoZone shipped free next day to me for $10 a piece. Sign up for the email and you usual get a free $5 or $10 off coupon.
There's also people that have done them without taking the intake or anything off. Requires some patience and probably a stool to reach around but you can feel where the coils are and remove them slowly to not drop anything. Seems difficult at the time but worth it to not take all that crap off and take more time. Happy wrenching.
There's also people that have done them without taking the intake or anything off. Requires some patience and probably a stool to reach around but you can feel where the coils are and remove them slowly to not drop anything. Seems difficult at the time but worth it to not take all that crap off and take more time. Happy wrenching.
Very easy to remove manifold.
Just take your time. and pay attention so nothing falls in the lower intake
Honestly, what I used to do was remove the upper and lower windshield cowls gives plenty of room to get back behind the intake manifold.
Just take your time. and pay attention so nothing falls in the lower intake
Honestly, what I used to do was remove the upper and lower windshield cowls gives plenty of room to get back behind the intake manifold.
Did my 2017 Highlander plugs today. 122000 km (76 000 miles), so a bit late. Took me 3.5 hours as a light duty amateur DIY mechanic, and never been that deep in the highlander. Followed the Car Care Nur step by step, and it was pretty straight forward. Hardest part was getting that 12 mm bolt at the back of the plenum to line up properly, but once it did the whole thing dropped in nicely. While I was in there, I cleaned the throttle body, cleaned the maf, and replaced the pcv valve ( original seemed to rattle just fine, but it's cheap insurance I suppose). The only thing that surprised me was the amount of sticky oil residue around some of the plug bases. Didn't extend to the threads, but it was a bit disconcerting turning the new plugs in as there was more resistance than seemed normal, in fact I had to use some slight pressure on my wrench to get them started. Was a bit terrified I was crossthrreading, but they seemed to go all the way in and torqued fine. Also, when I pulled the originals out, they were not tight at all. Maybe this is why there was the sticky residue? Never had any codes or running issues.
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That thought did cross my mind, but there really was no oil, as in wet. Just a very sticky residue on the bottom of the spark plugs ( maybe like there was some oil once and it got baked on.) I don't seem to lose a drop between oil changes. I'll keep an eye on the front 3 plugs since they are the easy ones to get at.
My time to start of this job, I 1st start by blowing away all the dust on the engine, then spared a de-gresser
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A spray down :
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B
Blower action :
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And then we keep the mosquitoes at bay with a fan , now it's clean ready to start , no sand is going fall in the cylinders.
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These new Lisle 37980 disconnect pliers ready make the job easy of removing coil cables :
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My surprise,
The 3 spark plugs I replaced tonight all had a gap of about .028 inches as opposed the .031 of new plugs !
Is that one of the reason why we are replacing the plugs so soon ? This is a 2019 with 96 000 KM so I am bit early.
New plugs :
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2 new plug top side view :
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Old plug, I would say the gap is at .028
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Now while at why not borescope and have look inside ?
Astro 24 mm nano socket, here we come
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That gave just enough clearance to turn over the crank bolt pulley topside :
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This was the big surprise, all 3 cylinders have what I think is major scoring, on the same side on all 3 pistons !
I have been using Pennzoil Platinum ultra with 8000 KM oil change interval, purchased this 2019 at 42 000 KM , 1st ower did the oil changes at the Toyota Canada 16 000 KM interval.
This was a surprise as I have not noticed any burning oil between changes. With this level of scoring this engine has to be burning oil.
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video of one of the cylinders :
I will tackle the 3 remaining when I get the gaskets from my local dealer.
A spray down :
Blower action :
And then we keep the mosquitoes at bay with a fan , now it's clean ready to start , no sand is going fall in the cylinders.
These new Lisle 37980 disconnect pliers ready make the job easy of removing coil cables :
My surprise,
The 3 spark plugs I replaced tonight all had a gap of about .028 inches as opposed the .031 of new plugs !
Is that one of the reason why we are replacing the plugs so soon ? This is a 2019 with 96 000 KM so I am bit early.
New plugs :
2 new plug top side view :
Old plug, I would say the gap is at .028
Now while at why not borescope and have look inside ?
Astro 24 mm nano socket, here we come
That gave just enough clearance to turn over the crank bolt pulley topside :
This was the big surprise, all 3 cylinders have what I think is major scoring, on the same side on all 3 pistons !
I have been using Pennzoil Platinum ultra with 8000 KM oil change interval, purchased this 2019 at 42 000 KM , 1st ower did the oil changes at the Toyota Canada 16 000 KM interval.
This was a surprise as I have not noticed any burning oil between changes. With this level of scoring this engine has to be burning oil.
video of one of the cylinders :
I will tackle the 3 remaining when I get the gaskets from my local dealer.
That is some concerning scoring. The piston has some play, do you hear any piston slap when you first start it on cold days? I'd just keep on the same oil change frequencies and monitor the level. Eventually it will start burning a little oil, but should have no major issues running it as you have. But the valves look good!
Some more info on the spark plug gaps my old plugs were still OK, Dealer printed out this page for my and he told me I was wasting my $$$ as in canada the service life for the spark plugs is still around 196 000 KM !
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Heck what's done is done I have gaskets now and I will be also cleaning the throttle body. Regarding the cylinder scoring I can only think of seized piston rings so I will be using some engine oil flush at my next oil change, I got a can of the Toyota branded product :
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Regarding the scoring I showed the service advistors the pictures at my local Toyota dealership, Last winter the engine was taken out for a second time to fix leaking gasket cover and cylinder head gasket ! Today when I showed the pictures the only person with an opion though this was normal for a engine with 200 000 KM but mine only has 96 000KM so. I purchase this vehicle used at 42 000KM and I had the original Toyota extended warranty transfer to me. but now I am wondering if that's the original engine ? I ask the service advisor and he says when the pull out the enging they don't examine SN to make sure it's still the original.
Regarding the engine at this point of time its smooth,quites on start-up and does not consume oil, So were it not for my borescoping adventure I would no idea of all this internal wear. I will start a seperate thread about scoring as its interesting and I will record the engine starting up. other can confirm if I really do have a quiet engine.
Heck what's done is done I have gaskets now and I will be also cleaning the throttle body. Regarding the cylinder scoring I can only think of seized piston rings so I will be using some engine oil flush at my next oil change, I got a can of the Toyota branded product :
Regarding the scoring I showed the service advistors the pictures at my local Toyota dealership, Last winter the engine was taken out for a second time to fix leaking gasket cover and cylinder head gasket ! Today when I showed the pictures the only person with an opion though this was normal for a engine with 200 000 KM but mine only has 96 000KM so. I purchase this vehicle used at 42 000KM and I had the original Toyota extended warranty transfer to me. but now I am wondering if that's the original engine ? I ask the service advisor and he says when the pull out the enging they don't examine SN to make sure it's still the original.
Regarding the engine at this point of time its smooth,quites on start-up and does not consume oil, So were it not for my borescoping adventure I would no idea of all this internal wear. I will start a seperate thread about scoring as its interesting and I will record the engine starting up. other can confirm if I really do have a quiet engine.
I always thought that if you could see the cross hatch through the scoring, it wasn’t considered significant. I’m definitely not an expert on that but I thought I’d throw it out there and let the experts correct me.
I didn't change mine till almost 100,000. They looked good to me and my mechanic said they could have gone longer, another 20K. The vehicle ran the same, before and after; so there wasn't any perceived performance drop. Mileage didn't change either.
Update I my job: I did it in 2 days, lower bank 1st, day 2 I did the rear bank you really need long arm, the real pain in neck is disconnecting the coil cables my new disconnect pliers did not fit way back.
I found the same level of scoring on the 3 remaining cylinders
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None of the spark plugs had the expected 13 Foot pounds of torque. I was very surprised they were loose like this. Notice these ones have the 'N' marking on them
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I did clean the entire plastic intake manifold prior to installing the new gaskets.
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Same with the throttle body is way pretty dirty clean for the both sides with the Toyota spray cleaner :
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Finished the job, was so distracted by the cylinder stuff I forgot about my wrench on the crank pulley ! Jumped up in terror on the couch went out and sure enough : That would have cause major destruction had I started the engine.
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Got all the plugs in at 13 foot pound or 17.63Nm using my accurate bike torque wrench, none of my automotive ones are accurate under 20 foot pounds.
My takeaway from all this I should have borescoped the engine right when I got this vehicle to establish the baseline. and especially before going in for dealer warranty work like the 2 times the engine came out to have timing cover gasket redone. The dual lens borescope are not that expensive and they just show you the RAW condition of cylinders.
Doing the job over 2 days was good in my case gave me time to process everything that was going on.
Some numbers you need to do the job from the care care nut video.
Coil bolts - 7 FT LBS
Spark plugs : 13 FT LBS
Plenum bolts and nuts : 15 ft LBS
I found the same level of scoring on the 3 remaining cylinders
None of the spark plugs had the expected 13 Foot pounds of torque. I was very surprised they were loose like this. Notice these ones have the 'N' marking on them
I did clean the entire plastic intake manifold prior to installing the new gaskets.
Same with the throttle body is way pretty dirty clean for the both sides with the Toyota spray cleaner :
Finished the job, was so distracted by the cylinder stuff I forgot about my wrench on the crank pulley ! Jumped up in terror on the couch went out and sure enough : That would have cause major destruction had I started the engine.
Got all the plugs in at 13 foot pound or 17.63Nm using my accurate bike torque wrench, none of my automotive ones are accurate under 20 foot pounds.
My takeaway from all this I should have borescoped the engine right when I got this vehicle to establish the baseline. and especially before going in for dealer warranty work like the 2 times the engine came out to have timing cover gasket redone. The dual lens borescope are not that expensive and they just show you the RAW condition of cylinders.
Doing the job over 2 days was good in my case gave me time to process everything that was going on.
Some numbers you need to do the job from the care care nut video.
Coil bolts - 7 FT LBS
Spark plugs : 13 FT LBS
Plenum bolts and nuts : 15 ft LBS
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