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I bought my 2010 Commander with the Hemi back in September. Ever since then I swore it had an exhaust leak sound coming from the drivers side bank. Dealer checked it out twice and found nothing. As a side note the service records show that it was always dealer serviced with no noted problems. On my own, I tried replacing the spark plugs, pressurized the exhaust system and a bunch of other things to no end. When driving next to a wall the exhaust sound was horrible.

This past week I used my homemade stethoscope (rubber hose and 1/2 copper tubing) on the exhaust manifold and isolated the odd sound to Cylinder #7. I decided to buy a new coil and 2 spark plugs from the dealer. Replaced them today and the leaking exhaust manifold sound is gone but I have the noticeable "hemi tick".

It baffled me, so I examined the spark plugs. One looked only slightly discolored and the other looked much dirtier. I decided to remove the boots from the coil and found to my surprise the spring inside one of them had been folded over inside the boot!!!! So the cylinder was only firing on one plug! I find it hard to believe it came from the factory like that, but you never know.

Good news is the leaking exhaust sound is gone and the engine has more power now! Just thought I would share as I have never run into something like this before. BTW: Never threw a CEL either, nor a stored code.
 

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Interesting....thanks for the info.
 

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Aha! I have a "Hemi Tick" on my new (to me) 2009 Commander Overland. Gonna check the plugs next weekend. I have been wanting to get under the plastic cowl since I got her last week.
 

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Aha! I have a "Hemi Tick" on my new (to me) 2009 Commander Overland. Gonna check the plugs next weekend. I have been wanting to get under the plastic cowl since I got her last week.
Welcome to the forum! I have the notorious Hemi tick as well but didn't think much about it since it seems to be normal. Maybe it isn't? Interesting find though.

I replaced my plugs this summer and didn't notice anything like that but maybe because I really wasn't looking for something like that. Was it completely noticeable? Is it something that someone would spot right away if they were changing the plugs? I can't imagine how it would've looked "folded over".
 

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I replaced my plugs this summer and didn't notice anything like that but maybe because I really wasn't looking for something like that. Was it completely noticeable? Is it something that someone would spot right away if they were changing the plugs? I can't imagine how it would've looked "folded over".
You would have to turn the coil pack over and looked directly up into the boot with good light to see the spring inside the boot.

I do when I change my plugs, I've never found one with a spring folded over, but sounds like its possible and I'll keep an eye out in the future.

My guess, the HEMI tick is normal, he might have had a slightly louder tick, and found a problem with the ignition that reduced the noise he heard.

I haven't seen a good explanation for the HEMI tick, I know the HEMI has a very stressed valvetrain and valve train does make ticking noises, especially at idle. So that has always been my guess, its the very tortured HEMI valvetrain you're hearing ticking.
 

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Sorry haven't checked in sooner.

Mongo: I discovered the folded spring on the coil pack side of the boot. On that side the coil pack has a round opening where the spring goes into the coil itself and the boot snaps around the outside of the molded plastic ring. My best guess is that when it was assembled, the spring was not lined up with the hole it goes into and got folded over into the boot on assembly.

The sound from that cylinder with a stethoscope was very different from the others. It sounded like an exhaust leak if you were standing next to the car. Best guess is that because #7 cylinder is at the end of the manifold it created an louder sound. Yeah, it was that noticeable.

Since discovery the engine has more pep and my gas mileage went up almost a full mpg to 14.6 (mixed driving).
 
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