I have a 2013 Honda Fit Sport with about 60k miles. The engine has been noisy as long as I remember, but I recently started to hear more noises such as a rattling at low rpm and also at high rpm. Also sounds like a possible exhaust leak under the car. Anyways, I was just feeling around the top of the spark plug coils behind the cowl while the engine was running and noticed that the #3 coil (from passenger to driver side) had a slight bumping sensation while all the other coils had no such feeling. Does this mean that the spark plug is loose which is causing it to hit up against the coil?

And just a PSA, if you noticed that your coolant reservoir is slowly losing coolant and can't figure out where the leak is coming from, replace the radiator cap. I noticed steam coming from my old cap after the engine was at operating temp and the new OEM cap fixed the issue.

 

Why not just check it out and see if you can turn the spark plug by hand without the wrench.

 

I will once I have the time. Didn’t have enough time to remove the cowl to get to the plugs today and I also need a socket for the spark plug. Just wondering if anyone noticed something similar.

 

Well, if it is as you suspect, then sooner or later, you’ll want/need to do a threaded insert. Either the reason it came loose, or after it came loose, the threads were probably damaged. The longer you drive with the loose spark plug, the worse the threads get. Not only will you get knocking, but eventually the engine can stall out. This happened to me.

Going further, if loose enough with a still running engine, it can get to the point where the threads can no longer hold the plug, and it shoots out the engine, breaking/knocking out the coil pack along the way. At least one other member had that happen.

If you’re lucky, it could be just the coil pack on top coming loose... that’s less damaging overall.

So yeah... don’t dawdle on this too long... you may regret it.

 

I would check them all immediately with the updated torque spec.

 

On a different car, we neglected to change the spark plugs; one plug worked itself loose, ejected from the engine and cost a lot of money to repair. Don't repeat that.

Note any updated torque specs for spark plugs.

Lots of good info on the forum here.

 

good advice, whether you do an insert or replace the head if there's damage. i know yuh already said yer checking it out. If you do wind up placing an insert I'd honestly recommend head removal to do it, see how deep the insert goes and how the plug sits.

A bit of funny info! worked on a 93 jeep cherokee 4.0 4x4 a little while back. Terrible design on the intake/exhaust. they're interwoven, both connecting like meshed fingers to the left side of the head of a straight six.
BUT it had a cast iron head!
I'd started it, revved, and changed its parking spot with the wires unclipped, loosely fitted over the plugs and said plugs being in no more than a full turn, nothing blew up (also likely due to bad rings/compression but WOW) To clarify, i'd set it up that way weeks prior so it wouldn't start, but would be sealed with the wires in order. I learned my lesson, of course, but I must say I'm impressed by cast iron.

 

So I was able to replace the spark plugs with a set of IK22 plugs. Plugs 1 and 3 were loose and I could remove them by hand. They also had some discoloration on the coils because the exhaust gases were seeping through. I tightened them by feel to make sure they were snug and used some blue thread locker to make sure they don’t loosen over time. Hope I don’t have to deal them for a while because it was a PITA to remove the cowl.

 

Looks like coil packs 2 and 4 (Unless you inverted the order on the ground) have a ton of the brown exhaust gas on them.. that tells me more about which plugs are leaking than the plug condition (all of which look somewhere between burnt and normal wear; it’s harder to see than in person i imagine).

For me it was plug 2. Now i check plug tightness for 1-3 every few months ... because I can check those “blind” without removing the cowl.

You should not have to replace your plugs again under most people’s vehicle life. Coils could still go bad. But people don’t seem to report failures except from the issue you just solved. (3rd gen .. different story)

Congratulations on completing factory assembly of your Fit! 😂