Ticking time bomb TICK TICK TICK: Spark plugs Alert Alert Alert!
- Thread starter 2001LC
- Start date
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OK - so its a few years late - but I just snugged up the RH bank to 17 ft.lbs too - all plugs still tight (#3 maybe moved 1/32 of a turn) - am happier with 17ftlbs torque (up from 15ftlbs original torque....)
My engine was making a ticking noise and I had initially chalked it up to a leaking exhaust manifold.
Upon reading this thread I checked my plugs and found all were super loose, not finger loose but well below the specified 17.5nm for sure; the previous owner had used a copper anti-seize on the plugs which I cleaned off.
I cleaned up the spark plug holes as the mating surfaces were all very dirty and I wanted to ensure the plugs would seal correctly, I used a rifle cleaning rod with a bit of shop rag covered in brake cleaner.
I also found cylinder 6 ignition coil boot was discoloured (overheated?) and that cylinder 4 ignition coil housing was cracked.
I tightened the plugs by feel and I think they're about 25nm, since test driving the ticking noise has reduced drastically and now I've narrowed it down to a leaking exhaust flex joint.
Thanks for this thread as I probably wouldn't have looked at the plugs for another few years at least.
Upon reading this thread I checked my plugs and found all were super loose, not finger loose but well below the specified 17.5nm for sure; the previous owner had used a copper anti-seize on the plugs which I cleaned off.
I cleaned up the spark plug holes as the mating surfaces were all very dirty and I wanted to ensure the plugs would seal correctly, I used a rifle cleaning rod with a bit of shop rag covered in brake cleaner.
I also found cylinder 6 ignition coil boot was discoloured (overheated?) and that cylinder 4 ignition coil housing was cracked.
I tightened the plugs by feel and I think they're about 25nm, since test driving the ticking noise has reduced drastically and now I've narrowed it down to a leaking exhaust flex joint.
Thanks for this thread as I probably wouldn't have looked at the plugs for another few years at least.
well done - you probably saved yourself a potential headache
So after reading this thread i immediately called the wife with the truck… took it bc it was last vehicle in driveway.
That said I bought an 07’ a month ago. Been doing fluids, belts, alternator, greasing, etc. But have recently heard a slight tick, tick, tick… I had already ordered Denali plugs and boot kit from rock auto last week. Just haven’t had a chance to swap them out w/holidays and what not. I thought at first it was exhaust manifold but this has me wondering.
The stories and tales told in this thread have me terrified… lol. Even though it’s not funny. Glad to read the warning by 2001lc.
That said I bought an 07’ a month ago. Been doing fluids, belts, alternator, greasing, etc. But have recently heard a slight tick, tick, tick… I had already ordered Denali plugs and boot kit from rock auto last week. Just haven’t had a chance to swap them out w/holidays and what not. I thought at first it was exhaust manifold but this has me wondering.
The stories and tales told in this thread have me terrified… lol. Even though it’s not funny. Glad to read the warning by 2001lc.
To the wise folks whom have had to work there plugs with 44k and penetrating oil…
Is the process to pre lubricate with small amount of penetrating oil and once plugs have been swapped fill a couple tanks up with 44k to burn off the oil?
Any particular penetrating oil to avoid or use?
Is the process to pre lubricate with small amount of penetrating oil and once plugs have been swapped fill a couple tanks up with 44k to burn off the oil?
Any particular penetrating oil to avoid or use?
I am extremely ticked off. Just completed a 3000 mile trip from Nashville,TN to Moab UT and back in our 2001 lx470. Spark plug blew out of the passenger side head today. Plugs and all coils were replaced 70,000 miles ago. I did not hear any ticking on cold start up and during our trip at every gas stop I would listen for a pop or ticking. Only once while idling on an easy trail did I hear a ticking and it went away and wasn’t heard again. The truck has 340,000 miles on it. I’ve always bragged on Toyota and I own 7 land cruisers from a 1966 up to this 2001 lx. But this is completely ridiculous. I was even considering putting a 2uz in my fj40 because of the reputation of the million mile motor. I’m so ticked I have kept up with maintenance and oil changes etc. Not sure what I’m going to do… replace the head or put in the diesel 1hd-fte I’ve always wanted or just get a completely different vehicle or maybe even switch brands. I’m just so disappointed. Truck is completely built and has been so reliable. I’m just thankful it didn’t happen in the middle of nowhere at night.
Jason
Jason
- Thread starter
- #548
Sorry to hear.
Which spark plugs (manufactures & type)?
@2001LC Denso bought from McGeorge/ourismon Toyota. Any recommendations on where to get a head? Haven’t done a research on head availability yet. Thanks for any help
Jason
Jason
The spark plug hole has no threads and don’t want to go the helicoil route so thinking a new or used head is my best route of repair. I’ll do the work myself. The diesel transplant is a pipe dream to do quickly. Better for me a cheaper to import an hdj100 and switch all my bumpers winch etc over to instead of a transplant
I know every vehicle has its quirks and issues especially at 24 years old and 340k on it but I’ve completely lost faith in the 2uz. Maybe I’ll feel better about it after a day or so. I guess if I replace this head I’ll just plan on checking spark plugs at every oil change. I’ve always worked on my own stuff for the most part and enjoy it. Used to do r&r at a transmission shop. Im not an expert and I’ve only rebuilt a 2f and a dirtbike engines. I don’t want a newer vehicle I believe they are mostly overpriced junk and I’d rather have or build something that I want than $pend money on some hybrid or turbo gasser they are building and failing. Sorry for the rant just trying to sift through this.
IME the 2UZ is one of the best engines ever made. A torque spec that's too low is a pretty easy issue to resolve. I don't understand the mentality at all, but I do understand the frustration. You can install a time-sert and be back up and running quickly with zero negative impact on the vehicle or engine. Then start tightening the spark plugs to 18 ft.lbs. Problem solved.
- Thread starter
- #554
Any used none VVt 4.7L 2UZ head, will work. Just do your home on engine. "Low, good oil change history, good air filter, no vacuum leaks. Have head inspected and tested.
Most do time-sert, in situ.
Safer on the bench (head off).
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This...
A time-sert is definitely worth a try, if it doesn't work, you are planning to swap the heads anyway.
awesomeissquid
SILVER Star
Can always pull the head to do the timesert and then if you need to swap it is already halfway there.
- Thread starter
- #557
If I had a blown plug, to deal with. I'd, Scope cylinders and do a compression test. I'd be looking for issues, like:
Metal in combustion camber and or any damage to piston, cylinder wall, valves & seats. Also compression test results. i.e. great, good, okay or bad.
I have seen a few where time-sert installed by a shop, in situ. In each case. Compression of just that one cylinder, failed testing. Both in being below minimum and differential greater than spec. Was cylinder damaged during blow out, or after time-sert in situ? IDK!
Metal in combustion camber and or any damage to piston, cylinder wall, valves & seats. Also compression test results. i.e. great, good, okay or bad.
- If any issues in cylinder. I'd work to install properly, proper type Time-sert in situ. Taking every precaution. To not, drop metal in camber and work to remove any I may have. "Do no harm"
- If no cylinder/head, has any issues of concern. A case of a well care for engine with good compression. I'd weight time and cost of removing head, vs in-situ repair.
I have seen a few where time-sert installed by a shop, in situ. In each case. Compression of just that one cylinder, failed testing. Both in being below minimum and differential greater than spec. Was cylinder damaged during blow out, or after time-sert in situ? IDK!
We've been get poor milage the last several months and I've been trying to figure out why. I know poor milage is a Land Cruiser thing but its gone from 13 mpg to 11 mpg. I thought maybe it was time for new spark plugs and then I read this thread and really got to worrying about my spark plugs backing out because I realized that I don't ever remember changing them. I've owned the truck for nearly 12 years and 140k miles. We are the 2nd owners. Bought it with 110k miles. I couldn't find in any of the paperwork we got from the original owner where they had changed the spark plugs either. So I finally got it done today along with changing the heater Ts for the 2nd time in our ownership. (Used brass this time.) Anyway, only 1 of the plugs was loose. 3rd cylinder back from the front on the passenger side was about a 1/2 turn from tight. All the coils and ruber boots looked good except the one with the loose plug. Have no idea how long its been loose or why it didn't continue to back out. Here is a picture of that coil. It has a small crack down it and is discolored. The ruber parts are hard, cracked and discolored as well. Should I replace the whole coil or just the boot and seal? I've had no check engine light or stumbling under load. Just the poor milage.
- Thread starter
- #559
Cracked coils, doesn't mean bad coil. But certainly not a good sign. In short, it's a good idea to carry a spare coil(s), if not replacing. At 250K mile, 25 yr, crack coils are found.
Cracks in coils, are a sign of excessive heat. Excessive heat is the enemy of coils. Which can, reduce effectiveness and life. Excessive heat is caused by; Excessive gap and or hot gasses escaping combustion camber.
MPG drop is often a mix of issues. Such as vacuum leaks, dirty or weak MAF sensor, spark plugs & coils, drifty or weak O2 sensors, low compression, overfill crankcase (oil), higher than spec oil, ATF, gear lube viscosity, tire pressure, tire size, body air flow alteration, etc.
Cracks in coils, are a sign of excessive heat. Excessive heat is the enemy of coils. Which can, reduce effectiveness and life. Excessive heat is caused by; Excessive gap and or hot gasses escaping combustion camber.
MPG drop is often a mix of issues. Such as vacuum leaks, dirty or weak MAF sensor, spark plugs & coils, drifty or weak O2 sensors, low compression, overfill crankcase (oil), higher than spec oil, ATF, gear lube viscosity, tire pressure, tire size, body air flow alteration, etc.
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I've got a couple I saved from my recent coil swap that are in decent shape, but maybe someone closer to you has one as well.
If original- the coil boots and the gasket can be replaced pretty cheap- Denso has a boot kit: part # 671-8184- you can find the Denso parts on Rock Auto for under $50. That will buy you some time. But eventually they will all start cracking. The Toyota coils arent cheap but I prefer them over the slightly lowercost Denso OES part. They are the same supplier to Toyota, but cant be sure if the parts are exactly same just in different boxes. There are counterfeits out there so if you buy new, buy from an official source (not amazon or ebay).
FYI There is a toyota parts sale on right now @ - 25% off the normal discounted price so its a good time to start buying a few or all of your replacement coils. The link to parts sale should be in a thread on the main 100 series landing page.
If original- the coil boots and the gasket can be replaced pretty cheap- Denso has a boot kit: part # 671-8184- you can find the Denso parts on Rock Auto for under $50. That will buy you some time. But eventually they will all start cracking. The Toyota coils arent cheap but I prefer them over the slightly lowercost Denso OES part. They are the same supplier to Toyota, but cant be sure if the parts are exactly same just in different boxes. There are counterfeits out there so if you buy new, buy from an official source (not amazon or ebay).
FYI There is a toyota parts sale on right now @ - 25% off the normal discounted price so its a good time to start buying a few or all of your replacement coils. The link to parts sale should be in a thread on the main 100 series landing page.