Ticking time bomb TICK TICK TICK: Spark plugs Alert Alert Alert! (6 Viewers)

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Hi everyone,

So my 100 blew out plug #5, mangled the plug and coil on a road trip, only to have it happen again a week later.

The threads on the spark plug hole are stripped for sure. Can’t get the plug to tighten.

Seems my options are a timesert or Helicoil. I’m gonna opt for the less expensive route, so timesert seems best.


Has anyone done it themselves? I’m able to do stuff pretty well, just.. haven’t done much myself in the past because I haven’t had my own garage space until now

(yay new homeownership and costly vehicle repairs).

The worst part of it that I heard the ‘Tick’ and assumed it was an exhaust leak I could ignore…. SMH. Pay attention to the tick!

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#5 Spark Plug blew out on our 2004 Land Cruiser too.
The shop used this repair kit: Fix-A-Thread Repair Kit M14-1.25
Been over a year and over 25K miles working without a problem.
Shop charged us just under $600 to do the work.\
 
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I have the slightest tick at idle from the passenger side, it sounds like a very slight manifold leak, but I have an 06. This thread makes me want to not start my 100 until I get all the plugs checked...
 
Hi everyone,

So my 100 blew out plug #5, mangled the plug and coil on a road trip, only to have it happen again a week later.

The threads on the spark plug hole are stripped for sure. Can’t get the plug to tighten.

Seems my options are a timesert or Helicoil. I’m gonna opt for the less expensive route, so timesert seems best.


Has anyone done it themselves? I’m able to do stuff pretty well, just.. haven’t done much myself in the past because I haven’t had my own garage space until now

(yay new homeownership and costly vehicle repairs).

The worst part of it that I heard the ‘Tick’ and assumed it was an exhaust leak I could ignore…. SMH. Pay attention to the tick!
Time Sert makes excellent inserts, well worth what they cost. The hard thing in your case will be executing the install, since you will be doing it blind. Make sure the piston is out of the way of the drill and seat cutting tools, and try to vacuum out the cylinder when you have completed the cutting operations. A small length of vinyl tubing taped up to a shop vac will work fine. Perform the vacuum operation BEFORE installing the insert so you have a bigger hole to work through. I have used time serts on 3 different engine applications with 100% success. Take your time, be methodical, be patient.
#5 Spark Plug blew out on our 2004 Land Cruiser too.
The shop used this repair kit: Fix-A-Thread Repair Kit M14-1.25
Been over a year and over 25K miles working with a problem.
Shop charged us just under $600 to do the work.\
I would do these all day for $600, seems expensive.
 
I have the slightest tick at idle from the passenger side, it sounds like a very slight manifold leak, but I have an 06. This thread makes me want to not start my 100 until I get all the plugs checked...
For real, go do it asap. Doing it yourself is easy. And if the (tick) misfire becomes more pronounced, stop driving :)
 
Time Sert makes excellent inserts, well worth what they cost. The hard thing in your case will be executing the install, since you will be doing it blind. Make sure the piston is out of the way of the drill and seat cutting tools, and try to vacuum out the cylinder when you have completed the cutting operations. A small length of vinyl tubing taped up to a shop vac will work fine. Perform the vacuum operation BEFORE installing the insert so you have a bigger hole to work through. I have used time serts on 3 different engine applications with 100% success. Take your time, be methodical, be patient.

I would do these all day for $600, seems expensive.
Thanks for your response. Planning on watching many YT videos before attempting myself.

Have you done them on a 100 series? Any recommendation on a specific kit?

I can prob google this but what do you mean by making sure the piston is out of the way?

Last Q - what’s the worst that can happen by my install? Aka what should I be very weary of?
 
For real, go do it asap. Doing it yourself is easy. And if the (tick) misfire becomes more pronounced, stop driving :)

I just checked all of them, nice and snug...it's coming from the passenger side, by the firewall. This miiiight be a lifter tick, but totally unsure.
 
Anyone with a tick. I strongly recommend replacing spark plugs ASAP. Then if tick remains, you'll know.
 
@2001LC What would be a give away with the spark plug, if anything (burned, smelly, etc)? Do you think I could swap the plugs from one cylinder to another for a quick check?

It’s not consistent every time the cylinder fires. It seems to go in and out of phase. It happens hot or cold.
 
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A tapping technique is put some sticky grease on the tap. Go a tiny bit each time and remove, wipe, fresh grease, repeat. Also vacuum after.

My helicoil installed by Joe at Colorado Toyota Specialists last year is still fine.
 
Like others have said Time-sert is likely to provide a better install over the Helicoil. Not saying the Helicoil is bad, just the Time-sert seems to provide more robust threads for extended use and repeated threading in/out.

Best way to install would be to remove the head and install on a bench so no debris has a chance to be left in the cylinder. Of course this adds a ton of extra work and comes at an added expense, so most just do it with the head installed. Be sure to remove all metal fragments from the top of the piston head before turning the engine over. If you don't there is a good chance the engine will be damaged in some way. The damage could be as minor as scratching on the cylinder walls reducing the engine efficiency or as major as damaging the piston head or valves requiring an engine replacement, ask me how I know.....

Whatever method you end up going with, I would highly recommend getting a borescope that you can stick down the tube after to verify everything is out. They have gotten significantly cheaper in recent years with ones that even connect to your phone.
 
@2001LC What would be a give away with the spark plug, if anything (burned, smelly, etc)? Do you think I could swap the plugs from one cylinder to another for a quick check?

It’s not consistent every time the cylinder fires. It seems to go in and out of phase. It happens hot or cold.
When any doubt, replace the spark plugs. Or re-torque the spark plugs at minimum. It's 1 or 2 hour of your time, well spent. As you do not want to deal with a blown plug. There is no reason for.

The tick or pop sound, is just the same as the sound of a cracked exhaust manifold. Where as a cracked exhaust, it not a dire concern needing attention today. The spark plugs are.

You'll not really smell or see anything, until coil removed. Then you'll see a cooked coil, browning or nice and clean. Depending on how loose plug is and for how long. Also, by first tightening as a test. If turns clockwise, it was loose

Swap plugs from one cylinder to another, does nothing. There are test for spark plug. First is gap. Second is spark.

Easy inspection:

On cold start up. Put your ear into fender well above tire, LH then RH well. Hear a tick, replace the plugs.
If tick still heard after warm-up. Shut it down and replace spark plugs before starting again.

Other ways easily hear tick/pop. Drive along-side a concert wall, with window down. Or Stand at curb as someone else drives away.

Tick Tick Tick and only when cold is not supper pressing concern, but get it done. POP POP POP after warm up, SHUT IT DOWN!

Tips:
Blow off head cover of any and all dust (sand)
Replace coil boot and top seal. Denso sell boot kit. We need to keep that top seal in good condition. It keeps dust & water out of spark plug tube.
Blow out (air pistol) spark plug tube, before removing spark plug.
 
Thanks for your response. Planning on watching many YT videos before attempting myself.

Have you done them on a 100 series? Any recommendation on a specific kit?

I can prob google this but what do you mean by making sure the piston is out of the way?

Last Q - what’s the worst that can happen by my install? Aka what should I be very weary of?
I have not used on 100 series.


You will be inserting tooling into the spark plug hole so you need to make sure your not damaging the piston with the tools. Yes you can use a bit of grease to help trap the metal particles, but it wont catch everything. I prefer to have the particles dry so that they can easily be vacuumed or blown out.

The main things to consider when selecting a Time-Sert is the length of the insert that you need.


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Like others have said Time-sert is likely to provide a better install over the Helicoil. Not saying the Helicoil is bad, just the Time-sert seems to provide more robust threads for extended use and repeated threading in/out.

Best way to install would be to remove the head and install on a bench so no debris has a chance to be left in the cylinder. Of course this adds a ton of extra work and comes at an added expense, so most just do it with the head installed. Be sure to remove all metal fragments from the top of the piston head before turning the engine over. If you don't there is a good chance the engine will be damaged in some way. The damage could be as minor as scratching on the cylinder walls reducing the engine efficiency or as major as damaging the piston head or valves requiring an engine replacement, ask me how I know.....

Whatever method you end up going with, I would highly recommend getting a borescope that you can stick down the tube after to verify everything is out. They have gotten significantly cheaper in recent years with ones that even connect to your phone.
A Heli-Coil is not appropriate for this application. I wouldn't use a Heli-Coil on any application that requires a seal. Even though the seat of the spark plug does the sealing, the Heli-coil is a coil of steel not a solid threaded insert. The last 3 threads of the Time-Sert are cold rolled. When the insert bottoms out on the seat, the installer driver forces those unformed threads into the base metal, effectively locking the fastener in place. The Time-Sert can only be installed as deep as you cut the seat, whereas a Heli-Coil could be screwed into the combustion chamber.
 
When any doubt, replace the spark plugs. Or re-torque the spark plugs at minimum. It's 1 or 2 hour of your time, well spent. As you do not want to deal with a blown plug. There is no reason for.

The tick or pop sound, is just the same as the sound of a cracked exhaust manifold. Where as a cracked exhaust, it not a dire concern needing attention today. The spark plugs are.

You'll not really smell or see anything, until coil removed. Then you'll see a cooked coil, browning or nice and clean. Depending on how loose plug is and for how long. Also, by first tightening as a test. If turns clockwise, it was loose

Swap plugs from one cylinder to another, does nothing. There are test for spark plug. First is gap. Second is spark.

Easy inspection:

On cold start up. Put your ear into fender well above tire, LH then RH well. Hear a tick, replace the plugs.
If tick still heard after warm-up. Shut it down and replace spark plugs before starting again.

Other ways easily hear tick/pop. Drive along-side a concert wall, with window down. Or Stand at curb as someone else drives away.

Tick Tick Tick and only when cold is not supper pressing concern, but get it done. POP POP POP after warm up, SHUT IT DOWN!

Tips:
Blow off head cover of any and all dust (sand)
Replace coil boot and top seal. Denso sell boot kit. We need to keep that top seal in good condition. It keeps dust & water out of spark plug tube.
Blow out (air pistol) spark plug tube, before removing spark plug.

Thanks for the detailed reply. I checked a few of the plugs on the PS side and all of them looked extremely clean, along with the coils boots and plug tubes. Everything was replaced roughly one year ago after the truck developed a misfire on #5.

Everything appears to be torqued down properly, however I went through and double checked. I did not inspect the DS side, as the tick is clearly coming from the PS side.

I've attached a video here, so you can hear what I'm hearing. It goes in/out of phase, so I'm not entirely sure. Hot or cold has to change. I'm hoping this is just a VVTi that my 2000MY didn't have, or some typical 2UZ "tick" that I forgot about.

 
Thanks for the detailed reply. I checked a few of the plugs on the PS side and all of them looked extremely clean, along with the coils boots and plug tubes. Everything was replaced roughly one year ago after the truck developed a misfire on #5.

Everything appears to be torqued down properly, however I went through and double checked. I did not inspect the DS side, as the tick is clearly coming from the PS side.

I've attached a video here, so you can hear what I'm hearing. It goes in/out of phase, so I'm not entirely sure. Hot or cold has to change. I'm hoping this is just a VVTi that my 2000MY didn't have, or some typical 2UZ "tick" that I forgot about.


The fuel injectors (FI) do tick. Some louder than others. Get a stethoscope and listen to them one by one.
If you've tech stream. You can also increase and decrease fuel to all FI at same time. This will help isolate also. As you'll hear pitch change.

Listening at fender well, hood closed on cold start-up. Help isolate both exhaust & spark plug leaks (ticks or pops). As sated: That and driving by a wall, or standing at the curb as someone else drive away heavy footed. Also as stated: we change plugs ASAP if this tick (tick or pop) heard. Since you've already replaced all plugs, assuming high confidence in torque and not bootleg plugs. Then a tick 98 out of 100 times (once plugs eliminated), is exhaust.
 
Over ten years as a dealer tech this is not a new thing, happens on other makes and models. Spark plugs are one of those items that should be tightened by feel (kinda like feeler gauges). You can tell when the threads bottom out and the crush washer collapses, then go a smidge more. After doing that try torqueing one to spec and you can easily see why they loosen over time if people use the torque spec. I'd say I've replaced thousands and have never had one come back loose.
 
Took out the coils and spark plugs last night from newly acquired 2004 LC with 299k miles. Boots were difficult to come out. I had to tear apart #1 but others eventually came out.
#5 spark plug came out with difficulty.
Compression tests were good across the board 170-180.
This morning, on my day off,I was to going to start on TB but decided to put a camera into #5. Then looked at the spark plugs closely and wholla. #5 came off with the insert.
I got some research to do as what kind of insert has been used and do it again. It seems like it is probably Time-Sert. This would be my fist time tackling such thing.
Any advise is appreciated.
Coils don’t look good for #5 and #7 as they are brown. Probably need some new coils and new sparks plugs even though spark plugs look fine and gap is good 1.0 (checked only couple)

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Took out the coils and spark plugs last night from newly acquired 2004 LC with 299k miles. Boots were difficult to come out. I had to tear apart #1 but others eventually came out.
#5 spark plug came out with difficulty.
Compression tests were good across the board 170-180.
This morning, on my day off,I was to going to start on TB but decided to put a camera into #5. Then looked at the spark plugs closely and wholla. #5 came off with the insert.
I got some research to do as what kind of insert has been used and do it again. It seems like it is probably Time-Sert. This would be my fist time tackling such thing.
Any advise is appreciated.
Coils don’t look good for #5 and #7 as they are brown. Probably need some new coils and new sparks plugs even though spark plugs look fine and gap is good 1.0 (checked only couple)

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Similar thing happened to me. In my case it seemed as though the timesert was not fully installed and when someone torqued down the spark plug it broke. How did the top of your piston head look? Any debris in there?
 
Similar thing happened to me. In my case it seemed as though the timesert was not fully installed and when someone torqued down the spark plug it broke. How did the top of your piston head look? Any debris in there?
I think looks fine based on the miles.
How did you fix it?
I probably need to purchase the kit and redo the thread,perhaps even go bit further. Maybe that is the problem for the insert not being set properly. I think we need 15mm insert and not 16.8. I was not ready for this challenge.

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I think looks fine based on the miles.
How did you fix it?
I probably need to purchase the kit and redo the thread,perhaps even go bit further. Maybe that is the problem for the insert not being set properly. I think we need 15mm insert and not 16.8. I was not ready for this challenge.

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Its a little hard to read from your images. You can read my thread here:
Tapered Seat Spark Plug Horror - https://forum.ih8mud.com/threads/tapered-seat-spark-plug-horror.1226940/

In my case the threads in the head were still sufficient to install a new spark plug. It seemed there was enough of a seal with the crush washer to keep the combustion chamber sealed. Unfortunately, I found metal fragments on the top of the piston and they had done their damage. The engine lasted another couple years after I bought it before I had to replace it. Tearing down the engine revealed the impacts on the piston had caused it to break apart. You can read about that here (see post #88 for the engine tear apart):
Misfire on Cylinder 8 and Oil in Intake Pipe -Investigation and Engine Swap - https://forum.ih8mud.com/threads/misfire-on-cylinder-8-and-oil-in-intake-pipe-investigation-and-engine-swap.1275437/
 

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