I just had a spark plug blow through the threads and out of my engine w/50k mi.
I have read several horror stories on the internet of this happening.
Honda is aware of this yet will not grant any good will toward fixing it.
Is this acceptable?
I was quoted $7000+ for a new head $3000+ for a used head and $1200 to helicoil with no guarantee whatsoever.
What would you do?
I'm in contact with Honda still.
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2011 41k Dependable 4wife Fun 4me.

 

The failure rate is astronomical!!!

Have you tried threading in a new plug yourself? Dealerships and repair shops are quick to recommend huge repairs without trying the simple task of threading in a new plug.

Good friends '09 blew the plug out and we cleaned the threads and installed a new plug with a light dab of anti-seize. Only about 5,000 miles since we put 4 new plugs in and one new coil, but so far so good.

 

Wow that sucks... Does this affect all model years? My Fit is a '13 and a little over 50k miles and I'm still paying it off. Is there something I can or should do as preventative maintenance?

 

I believe you could check your spark plugs to see if there are tightened down properly.

 

I don't know where those quotes came from but for 7K you can have a new engine..

A helicoil should be < 200 bucks installed. (Its about 2 hours shop time to do the work.

You need to find a independent Honda shop, or good import mechanic, I got consistent quotes of about 2300 to do the head gasket in my GD.. So I did it myself.. Took a Saturday on two weekends to do. (Took the head to the machine shop to get it surfaced)

If the head is pulled off, a good cylinder head shop can put threaded sleeves in the head or weld and redrill/rethread the hole

 

honda parts now has a bare head for about 800 (New) and a loaded head for 3000 which is stinking ridiculous. But sounds like they want to charge you 3K for the head and 4000 to install it? dang I'd do those every day... No wait,, I'd do one every other week and have fun the rest of the time..

 

My #2 & #3 plugs came loose on a 2011 Sport AT around 40K miles. I installed new plugs and properly torqued but came loose again. Used blue threadlocker from Permatex. Now at ~67K miles without anymore problems.

Are the threads on head "really - really" gone?

 

I wonder if there is any mechanical way to lock the spark
plug and prevent it from loosening. Something similar to nuts on aircraft engines.

 

I read that the torque spec for these spark plugs is only 13 lb/ft. So I guess they should be pretty snug but not too tight. I will be checking them out tomorrow. Taking off the plastic hood cowl and metal sill took more work than I anticipated.

 

If the factory tightens to 13 FT/LB, that's the root of the trouble. Various spark plug manufacturer websites show a higher torque for plugs this size, all between 18-22 FT/LB in an aluminum head. I'd definitely go with that (mine are torqued to 22) and using spike55 bmw's tip, a bit of light duty threadlocker can't hurt.

 

my '09 just did the same thing roughly same mileage (110k km).
Dealer first tried new plug, wouldnt thread.
Helicoil -> but low compression on cylinder
Now looking at replacing engine. Warranty is gone as it is a '09 above 100k
Work so far is under $500 (diagnostic, parts, labor for helicoil)
I talked it over with my dealership, and they are unable to cut a break, we both agreed I should call Honda Canada.
Currently case is being reviewed.

I would think the pricing you got seems very steep...
I would think a call to Honda customer relations should help. Calmly explain what happened with your car, mileage, your service records, etc. If you have done all maintenance thats a plus. Was the car bought from Honda, or used via private sale? Mention you don't think it is reasonable for this type of failure to occur at such low mileage. Stay calm and collected, and hopefully they will escalate it and get it investigated.
Best of luck!

 

Thanks for the tips. All my 4 spark plugs were snug when I took them out. Used a bit of threadlocker before I put them back in. The torque wrench I had only goes up to about 17 lb/ft but I over tighten a bit more to get close to 22. I think the stock plugs last 100k so hopefully I won't have to touch them again till then.

 

Just found it blown out after it sounded like a helicopter. Was able to get it home and it had smashed the plug on the bottom side of the wrench entry way. Thought the cylinder had smashed it but I was able to get another spark plug in there. I might try the blue thread locker technique for now. The only problem with that idea is the coils are darn expensive so each time it blows it's going to be some odd 100 bucks and a lot of time. I want to Helicoil it but I don't trust 1/2 of the kits out there. Might send it to the mechanic if he will do it for around 200. Honda is really not deserving of my future business due to this issue and the lack of owning up to their failure to engineer this thread to hold the plug for the life of the car.

Shame on Honda!

 

I have new plugs and coils to put in, but I still have the original ones with 148k on them still running.

 

Count yourself lucky! My friend made it to 124k. Then, boom!

 

Have to update this...blew out again and took the threads with it. We pulled the head and had a machine shop helicoil all 4 plug threads. Not a fun or easy job.

 

Are there any warning signs that an owner should be aware of?
A difference in engine noise or performance?
Or is it too late by the time you hear anything?

 

Listen for any slight mis-fire. Ours gets a very slight mis at idle when the plug is loose.

Others have reported a fuel or exhaust fume odor from the front of the car.

 

I had no gas smell... but at idle it would get a little rough. The problem is that if you do not read the forums, the rough idle is so slight that you dont worry about it... you could chalk it up to bad gas, cold morning, etc.
As soon as it feels funny, or strange, have it checked out.

 

Completely agree! I heard the miss, but didn't have a clue what it was since that was before this was a known thing.

Only reason I found it is that I decided to replace the plugs to try to fix the slight miss at idle. That's when I found one was part way out many moons ago.