Well this morning I had the spark plug blow out on cylinder #3. Heard a very slight ticking coming from the engine bay, then all of the sudden pure cylinder noise. Knew exactly what it was once I heard it. Ironically happened on my drive back from the title office where I had just given them the lien release for my car so I can get a clean title with just my name. No joke - just payed the car off over the holiday break, now this.

The spark plug didn't actually BLOW out of the socket, the coil pack was still bolted on, but when i removed the coil the spark plug came with it. Threads on the plug didn't look all that bad, but I tried to thread the spark plug from cylinder #4 into the well of #3 and no. go. So I guess I'm Helicoiling tomorrow, right? I work for an auto parts supplier so I can get the new plug, coil, and Helicoil kit for a great price, so there's the upside. Major bummer though.

I've read a few articles here on the forums of people having the same issue on the GE, primarily cylinders 2 and 3. Oh well, guess I can join the club.

 

It sounds like the threads in the head that hold in the spark plug just gave way. I believe the head is aluminum and the plug is steel so the head is softer but it does not seem like a reasonable or acceptable thing to have happen at all. Why do you think this happened?

 

MEATBABY,

That sucks man!!

I suggest everyone to check the tightness of their spark plugs from time to time (every 30k miles, every 2 yrs etc., whatever is comfortable for you.)

I was doing maintenance codes B1 4 at 102k miles this past weekend. Although the spark plugs from cyl. 1 to 3 felt ok in terms of breaking it loose, cyl. 4 felt way too easy. I honestly thought that I would see some combustion leakage on the spark plug and coil pack. Good thing it was still tight enough to hold its seal.

 

Well I better check mine soon... and gives me a reason to upgrade to the colder IK22 plugs!

 

Crisis averted. Helicoiled it myself, put in a new NGK spark plug and Hitachi coil, runnin great now. Sheesh. I kind of want to Helicoil all of the spark plug ports now, since the sleeve that goes in is steel instead of aluminum. How do manufactures not just make the entire spark plug well and port steel from the factory to prevent blow outs like this? I suppose it's just cheaper.

 

Crazy I just checked my spark plugs today and they were loose. I wonder if that was causing my cel light and misfire on cylinder 3. I had the code before and changed all 4 coils and plugs but code came back with in a few days so I checked my plugs and they seems loose.

 

Are you guys using torque wrenches or going by feel?

 

So is the thought that the plugs blow out because they were loose and not tightened enough, or that they blow out because the threads in the head were damaged because they were tightened too much? Or is the design just bad?

 

Running with a loose plug, the plug vibrates hard with every combustion event, and eventually it wears down the aluminum threads -- until the plug can be ejected from the hole.

 

Use a spritz of carb cleaner and a brush to clean the hole and the seat the plug tightens against when changing plugs. Read the tightening instructions on the plug box.. Many don't.

If you can't spin the plug down fully with just the extension the threads are not clean enough..

 

^ Good advice. Another great piece of advice is GET A TORQUE WRENCH! Don't use "feel" or any other "rule of thumb." You'll need a torque wrench that A) is short enough so you can actually fit it in the engine bay and use it in a practical manner, and B) measures in small enough numbers for the proper torque required. In the case of our cars, and a lot of Hondas for that matter, the proper torque for the spark plugs is 13 lb/ft. A torque wrench with a lowest setting of 20 lb/ft will obviously not work.

Whether or not it is beneficial to use lube or anti-seize on spark plug threads seems to be a really debated topic, so do what you want. Be sure to not get anything on or near the electrode of the plug. I do use dielectric grease. Apply some to the opening of the coil pack where it meets the terminal of the spark plug. Don't try and put the grease on the spark plug first because it will most likely just be taken off by the socket you use to tighten the plug. Putting the dielectric grease on the coil before you slide it onto the spark plug ensures you're not wasting the grease.

 

Also checking the coil packs and torque on the spark plugs regularly is a good idea. It's just a shame the spark plugs on the Fit are such a pain to get to.

 

I just had the same thing happen today in my 2011 sport, except cylinder 2. My mechanic didn't want to touch it, he didn't see how he could get a drill in without dropping the engine. If you managed to accomplish a helicoil tap with the head on, can you tell me how you got room to run the tap?

 

Torque wrenches are your friend.

I used to work where we had guys who assembled hundreds of bolts in equipment that had to be torqued. These guys had a lot of experience in assembly probably thousands of fasteners per week.

We had a class where they were showing us how to use some new tools and the guy brought a gadget with a socket wrench and a bolt head, it had a display he could cover up. He bet us that Nobody in the room could hit 30 lbs +- 2 lbs of torque by feel. out of 80 guys 1 did it. And he was the guy who calibrated our torque wrenches..

FWIW on some race engines the fasteners are assembled with degree wrenches, you torque to a base value like 10 inch lbs, then you turn the fastener a specific number of degrees to set its torque, the thread pitch and fastener size have to hit a torque value. Assumptions are that the bolts are new very high quality and all threads are lubricated.

 

Does this happen with any other car? It is the 3rd plug on my 2012 Fit that came loose at 40,000 miles and again at 85,000 miles. I still have payments on the car, can I get honda to pay for the damage to the engine? Does anyone know how I can submit a claim?

 

If you have documentation that the plugs came loose at 40K miles and repairs were made and it happened again at 85K miles, then you might have a chance. Try and see if the dealer is willing to help you out. Then call the corporate office of Honda if you are not satisfied with what the dealer suggests.

 

This is a flip side of having extended service (100 k) plugs in the aluminum engine. It looks like spark plug gasket metal coating (?) of original plug "welds" to the seat leaving scored surface after removal (I saw this on my car).So the solution is to either installing a new plug with fresh gasket hoping it will deform aluminum while crushing thereby creating good seal and retention or to "condition" the sealing surface using appropriate tool (which will create chips of abrasive material that can fall into the engine).
One car flipper used aluminum repair epoxy to "forever seal" the semi stripped plug in the head and then sold the truck; the plug ejected again 2 month later (I helped with the head replacement on it)
So the bottom line (humorous advice :
don't keep the car over 6 years
don't change plugs before 100 K
lease electric car if you can afford
get smog exempt vintage import with points, condenser, push rods, carburetor, annual spark plug replacement and valve adjustment and be a man!

 

Thank you. I work in an enormous factory with miles of piping and thousands of pipe flanges and valves. Same scene at my place as yours. We had far too many gasket leaks following work by workers of all ages and experience levels "who could torque bolts by feel". Right. Torque wrench use became mandatory and success was quickly found, with significantly fewer leaks. Yes, torque wrenches are your friend.

I aim to check the plugs in my 2013 when I can find the time. At my pace, accessing them looks like an all-day affair.

 

Heard some people just reach around from the passenger side with their left hand and get back there.

Also, youtube vids about removing the wipers, cowling, and wiper motor assembly to get in the top side.

 

I started getting CEL around 26K miles (winter). Came up misfire in #2. Dealer says coil pack. Nearly $300 later, I ask for the bad coil pack. Smells like gasoline. 2 days later, CEL back on - misfire in #2 and #3. Dealer says bring it back to change another coil pack after $50 diagnosis, $168 coil pack, and $50 labor - No Way! Scratching head, why something outside of engine smells like inside of engine. Reached in passenger side with left arm, undo #1 - normal resistance, #2 - lose, #3 - lose, #4 - normal resistance.

Jump to the end - blue threadlocker on all plugs. 61K on it now and using all original coil packs. Never was a coil pack issue.