Spark plug worked itself free!

[t-rd]

I have a 2007 v6 with 85600 miles on it, the engine has never been worked on except for oil change. I ordered some Denso Iridium IK20 spark plugs so I decided to put them in today before the 100k miles replacement as recommended by Honda. To my horror, the middle spark plug in the front bank was not tightened AT ALL. I went to unscrew it and it was already loose! I literally just placed the spark plug socket (with rubber inside) and pulled it out. The end of the coil pack along with the back end of the spark plug is soiled with a mix of dirt and oil. I've never had this happen before on any car. So my question is whether someone got lazy at the assembly line at the Ohio plant or the spark plug actually moved itself out over time? I'm surprised I don't have a check engine light but I did feel the rougher idle. The morale of this incident is that you should check your spark plugs every so often.

[Accordriver]

Originally Posted by t-rd

I have a 2007 v6 with 85600 miles on it, the engine has never been worked on except for oil change. I ordered some Denso Iridium IK20 spark plugs so I decided to put them in today before the 100k miles replacement as recommended by Honda. To my horror, the middle spark plug in the front bank was not tightened AT ALL. I went to unscrew it and it was already loose! I literally just placed the spark plug socket (with rubber inside) and pulled it out. The end of the coil pack along with the back end of the spark plug is soiled with a mix of dirt and oil. I've never had this happen before on any car. So my question is whether someone got lazy at the assembly line at the Ohio plant or the spark plug actually moved itself out over time? I'm surprised I don't have a check engine light but I did feel the rougher idle. The morale of this incident is that you should check your spark plugs every so often.

Very scary. We had someone report a similar incident not too long ago...

[Sultan]

beyond crazy how many times has this come up before on the forums

[t-rd]

I can tell that cylinder has been running lean because that one plug is clean around the round edge while the other plugs have the usual carbon deposit from normal burn. Looking at the aluminum rings at the seat of the plug where it should have touched the socket, it looks brand new with no sign of it ever being torqued down into the socket. My gas mileage might actually improve without that cylinder's injector dumping extra fuel for a normal burn.

[PKile]

Did you notice any driveability problems, like roughness at idle or lack of acceleration? I would have thought a loose plug would result in a drop in compression and you would have noticed the car was acting like a "5-cylinder".

[t-rd]

Originally Posted by PKile

Did you notice any driveability problems, like roughness at idle or lack of acceleration? I would have thought a loose plug would result in a drop in compression and you would have noticed the car was acting like a "5-cylinder".

Not at all until recently I noticed the idle is a bit rough. No acceleration problem either. I bought the car used with only 4900 miles on it and the spark plugs were never removed during my ownership until yesterday and that's what I discovered. The plug might have been "lightly tightened" then recently just got to the point where it was at. I just don't see it moving itself out even if it's hand tightened with half a turn.

[CarlR33]

Who knows what could have happened in the 4900 miles before you got it. Yea, the plugs should not have been out but who knows.

[richpor]

Originally Posted by t-rd

I have a 2007 v6 with 85600 miles on it, the engine has never been worked on except for oil change. I ordered some Denso Iridium IK20 spark plugs so I decided to put them in today before the 100k miles replacement as recommended by Honda. To my horror, the middle spark plug in the front bank was not tightened AT ALL. I went to unscrew it and it was already loose! I literally just placed the spark plug socket (with rubber inside) and pulled it out. The end of the coil pack along with the back end of the spark plug is soiled with a mix of dirt and oil. I've never had this happen before on any car. So my question is whether someone got lazy at the assembly line at the Ohio plant or the spark plug actually moved itself out over time? I'm surprised I don't have a check engine light but I did feel the rougher idle. The morale of this incident is that you should check your spark plugs every so often.

I often like to loosen something off when i sell a car... spark plug, brake line, driver's seat bolt, glove box hinge.. Put a new one on, tighter 'er up and go for a boot and enjoy your new found cylinder!

[BLCKFLSH]

I replaced my plugs a week ago, and I forgot to plug one of the coils back in. The engine had a little more shake to it, and the check engine light came on, but it didn't run as bad as you might think it would missing a cylinder. Hooked the coil up, check engine light didn't come on, and everything was cool. The Denso plugs looked pretty good after 82k miles. There was a very minor improvement, with the new NGK plugs, but I think the Denso plugs could have been fine for another 20k.

[yi3o8]

I don't mean to resurrect an old thread, but this has me worried a bit.

I just did my plugs at 95k, and it was needed. Switched to the NGKs and they seem good.

However, I didn't have a torque wrench under 20lbs and so I got them snug and then turned them with slight pressure with the ratchet, stopping when it felt like I was forcing it (I know that's vague and subjective - but about a qtr turn maybe)

Anyway, to test it I went to loosen the plug and it came undone fairly easy compared to the factory plugs. I chalked this up to the factory plugs being in for so long, but do I need to worry about them being too loose? If I check a couple plugs in 500 miles will that be good enough or do I need to worry about them coming all the way out like this?

[BLCKFLSH]

I don't remember any of my plugs being loose, but I did notice some crud on the threads of some of them. Maybe a couple were not very tight. I did torque the new plugs, but I will definitely check them again soon. I think as long as the plug is firing, and holding at least some compression, the check engine light would not come on. By the time the check engine light would come on for something like this, it would probably be too late.

[yi3o8]

Thanks for the response. I wasn't really worried until I read this, and I'd never heard of plugs coming loose. Just thought they needed to be snug and to worry about stripping them.

I'll check them in awhile to see.

[Sparkland]

It seems some of the Ridgelines with the V6 are having the very same problem with cylinger #4. In at least 3 cases the loose plug caused engine damage. No one is sure why the plugs are loose after being tightened to specs.

I would suggest everyone with a V6 should check plug #4 immediately.

Brad

[yi3o8]

One thing that confuses me, is does the crush washer get affected by checking the plugs?

[BLCKFLSH]

Originally Posted by yi3o8

One thing that confuses me, is does the crush washer get affected by checking the plugs?

I would apply maybe one or two more footpounds when re-installing, but as long as the washer is not damaged, it should seal just as good.
When you are not using a torque wrench, some manuals say to turn 3/4 turn after the washer contacts the head. If the washer is already compressed, obviously it would not take as much turning to get the correct torque. Probably 1/2 turn or less would get you the same torque.