Rattle from engine when accelerating (sounds like keys)

[Higher_Ground]

Yeah it's still there, must have just been hard to hear yesterday.

I don't doubt that there's a problem, but I'm not really sure how to go about getting it resolved other than perhaps catching it on video.

I am no mechanic and just going by what I read here. I suppose it could be any number of issues and I would not know where to start.

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[Scrubb84]

Yeah it's still there, must have just been hard to hear yesterday.

I don't doubt that there's a problem, but I'm not really sure how to go about getting it resolved other than perhaps catching it on video.

I am no mechanic and just going by what I read here. I suppose it could be any number of issues and I would not know where to start.

The biggest problem I find with this issue is trying to get a dealership to fix it. I dont know how your service guys are, but mine can’t even do an oil change properly. Seems to me that they are trained to deny any warranty work at all costs and blame manufacturing problems on gigantic 35” tall tires. Even if they attempted to actually fix it, they are so incompetent they wouldn’t know what to do or where to start. Not to mention they can’t even follow step-by-step instructions written in big bold letters on a TSB. It’s almost comical.
In a laughing while crying kinda way.

 

[ShadowsPapa]

Part of it is regional, part of it is the size of the shop, how it's managed and so on. I've found that if I get the ear of a service advisor, and I've learned to try to work with the same ones I've dealt with in the past, and get buy-in for a problem, in a couple of cases they went right by the guy I assume is "their boss". I know with the tonneau cover issue there was a lot of push-back from the service writer I had been "assigned to" and even their manager was pushing back with "they're all that way" and that sort of BS until I showed pictures from this forum and some of our discussions here and there was enough of a huddle by that time another guy back there was listening - and decided to "walk by" and speak up - "yeah, they have a whole online team dedicated to these things and I've heard about this issue before - finally they agreed to contact the star team. I got a new cover.
I also got some attention next time I went in because they knew my background and that there was a huge audience out here in the WWW and especially on this forum.
I typically go in with a note and bullet points showing my research, and applicable service bulletins, any related posts from here....... and like when I call tech support about anything else, I bypass the initial help desk level of is it plugged in, is it turned on.
When I took my wife's Jeep in for a misfire - I had a multiple page printout of the misfires with all of the vehicle's environment displayed - fuel level, air temp, open or closed loop, and much more - and it specifically stated "misfire cylinder 3 ignition". They couldn't ignore that.

Can't always do that with issues like this because, as with the misfire, they are a lot more complex than 30 years ago and there are multiple possible causes. The valve timing is not static, the valve lift is not static, and if you had a Mercedes, even the intake runner volume isn't static.
These issues are also fleeting and if there's not a related misfire or other error condition, the ping or rattle likely won't be recorded anywhere. In a way I wish mine would do it just twice so I could connect in and get a report of the conditions at that time. Once to show me it was happening, time to connect up and log things, then the second time so I could log it. So just twice LOL

 

[Higher_Ground]

I do appreciate all the advice.

One thing I do not know, is how serious of a problem is this? It's very brief and hard to hear. Is it something I could monitor for damage or have a dealer check on?

If this is a problem that is unlikely to cause catastrophic damage I would like to not worry about it.

 

[ShadowsPapa]

I do appreciate all the advice.

One thing I do not know, is how serious of a problem is this? It's very brief and hard to hear. Is it something I could monitor for damage or have a dealer check on?

If this is a problem that is unlikely to cause catastrophic damage I would like to not worry about it.

Brief and light ping isn't normally an issue. Prolonged, or constant is a problem. Loud is a problem, if it's real easy to hear it's not likely a problem.
It can never hurt to have it on record as being reported to a dealership - but if you have to listen closely and it's only under certain conditions for short times - I'd personally not get too excited about it.

 

[flipmode]

Okay Gang, a long update:

I spent some time this weekend after gathering parts and materials for a few weeks, and tried to attack this problem with solutions I thought were applicable. I'll try and keep it concise, but I wanted to share a few things I observed along the way, as well as just some general understanding of what I believe the issue to be- maybe it will be helpful, maybe not, maybe it will spark some additional ideas.

TL:DR, I did a bunch of stuff with no positive affect on the rattle/knock, at the very least we can mark these things off in our elimination process.

1.) Replaced Park Plugs

I learned per the TSB posted earlier (thanks @Hootbro ) that my gladiator has potentially damaged spark plugs from the factory, so I thought I would take this on first. I cannot understate how unreasonably complicated this process is, and a total PITA. Just here to validate what others have said about the topic.

After installing the new spark plugs (I just used new OEM ones), I noticed my engine ran notably smoother than before. There was a slightly rough idle (and I mean very slight) that I had noticed for some time. I had also noticed and reported to my dealer a very slight (emphasis) stuttering when accelerating at low speed or at highway speed. This at least, is resolved by replacing the spark plugs. Power delivery is much more consistent and idle is perfect, almost can't tell its running. This is how I remember it the day I picked it up. I realize I am running the hazard of placebo affect here, but I'm gonna stick to this, I think it was an improvement.

Old Spark Plugs:

2.a) Ran BG EPR Cleaner Through Engine

During my searching for a solution, I discovered a product by BG that is allegedly helpful with cam phasers when they become 'gunked up'. There is a very fine mesh cover over the internals and this is supposed to help clean that up.

2.b) Changed Oil

After running the EPR through the block for about 10 minutes, I drained the oil and replaced the filter (as is called out by the BG instructions). I replaced the oil with Amsoil 0w-20. From what I can find this has the lowest NOACK volatility test (8.5%, let me know if you found one lower at this weight). Also replaced the filter, just used the Mopar one, Amsoil filters are on backorder currently.

3.) Installed an Oil Catch Can

After reading about the purpose of this device, seemed to make sense to address detonation. (insert clever segue here)

4.) What I've Observed Along the Way

While swapping the spark plugs, when I finally got the upper intake plenum removed, I had it propped up to one side of the engine bay, and I noticed almost immediately it started leaking oil through the front of the throttle body. To much oil in my opinion. It dripped out about enough to fill a shot glass. Of course this probably wont surprise some of you, as the engine recirculates whatever the block vents to the intake plenum.

• I've used the dealership for oil changes so far, I don't really know what type of oil they are using, assuming spec weight- but I don't know at what temperature its rated to 'evaporate' or otherwise become aerated and get exhausted to the intake plenum. This, combined with the fact that they consistently put 6 quarts in, when 5 are specified (I've reminded them twice). I wonder if this has some affect on what is vented. More oil, more material in vent to plenum. I just cant know.
• Also while swapping the spark plugs, I noticed that they were coming out, I'll call it 'wet', with a little oil on them. If it is oil, this supports the idea that whatever is venting to the intake plenum is making its way to the combustion chamber.
• It would seem, that the oil vented to the intake plenum is becoming an additional combustible material, causing either detonation, or pre-ignition. The oil lowers the octane of the air/fuel mixture being burned, and might cause the knock. I mention octane, because if I run 87 fuel, the rattle is louder and prolonged. I regularly put in 92, and the rattle stays within its original RPM and speed range. I was also able to notice over the course of a week, that after a cold start, I can drive until the engine exceeds 176 degrees (obviously this is a a range, who knows if the cluster gauge is actually accurate) without the rattle, above about 176 degrees it will rattle as expected.

I wasn't able to clean out the oil from the intake plenum, I just let as much drip out as I could, with the throttle body closed. I'm sure there was still some in there. I drove about 132 miles total after doing all this work, hoping that it would blow out and burn any remaining oil in the plenum and whatever is now being vented would get caught by the catch can.

5.) What to do Next

I have no idea. I'm convinced its detonation or pre-ignition, and that there is oil making it to the combustion chamber. Now I am worried its something more serious than I originally thought. Leaking head gasket? Bad piston rings? Who knows. Am I obsessed with this? Maybe. There is no CEL, ECU code, or anything to suggest there is a problem. Just an obnoxious rattle that should not be there in a 6 month old truck.

I'll keep digging and share the results if they are useful.

Thanks All!

 

[legacy_etu]

^^ nice job. I hope your in better shape now. One thin g, I hope you double checked the gap on the new plugs before putting them in. I've seen new plugs with gaps not to spec. on them.

 

[93civej1]

Well this is probably a consequence of the latest software update. It pulls back on the misfire detection to keep the avengers light at bay. The problem is the VVT tables are for the wrangler and are marginal for the Gladiator. On top of that the phazers can get stuck or dirty and things get real ruff. First thing to try is a fresh clean oil change with good oil and see if the dealer will run the phazer cleaning process with the starscan tool.

Im wondering that. As of lately i had work done on mine with up to date flashes and having the TSB done. Now I have recently noticed I am getting this pinging sound as well. I thought it was sound from the trans, but it does indeed sound like it is detinating. I had never noticed this until the other day. Its not often but ive heard it a couple times now.

 

[93civej1]

I do wonder if the latest update had anything to do with it. They supposedly did a software update to mine when they did the steering box.

Same here.

 

[iGlad]

You have problems if higher octane fuel resolves a noise. The resolution is for them to fix it, not for you to keep buying expensive fuel that otherwise has no benefit.

I ran 91 for a bit about 10k miles and noise never went away. Went back down to 89 for now and have another service scheduled to find the problem.

What are you thoughts on an oil catch to potentially resolve this problem? @ShadowsPapa

 

[93civej1]

I ran 91 for a bit about 10k miles and noise never went away. Went back down to 89 for now and have another service scheduled to find the problem.

What are you thoughts on an oil catch to potentially resolve this problem? @ShadowsPapa

i dont see that a catch can will do anything to reduce your rattle. its purpose is to catch blow by from going back into the intake.

 

[ShadowsPapa]

I ran 91 for a bit about 10k miles and noise never went away. Went back down to 89 for now and have another service scheduled to find the problem.

What are you thoughts on an oil catch to potentially resolve this problem? @ShadowsPapa

I have two thoughts on this -
Oil in the combustion chamber can cause detonation, or make it worse.
and
It should not be necessary as any manufacturer should have the oil baffled and filtered out of the air before it's purged or pulled from the crankcase.
Much of what is seen in SOME of the catch can pictures/videos I've seen isn't necessarily pure oil - it's often large in volume due to moisture. When I see contents that aren't the exact same color as the oil in the pan, when it's lighter color, milky, etc. - it indicates they have caught as much water as oil if not more. But then I've seen some where it is indeed more oil than anything.
So I've seen a mix - some claim they are catching huge amounts of oil when they are not, others are catching oil.

It would be interesting to see if such a device has any impact on the ping of detonation.

Another thought is -why do tens of thousands have no ping, and no catch can, and have no problems while others swear that MUST run such a device and are catching soooo much oil. Well, if that was all oil, then their sump would be down by the same amount and very few ever say "I pulled out a pint of oil and it was low by a half quart.
It's not making oil so for every cup caught the sump has to be down by that much.

So I have mixed feelings - I feel it's often over-hyped especially when people are just running these things on the level, on the street and claiming big amounts of oil caught, but it's not pure oil and the sump level never drops.

But I've seen some serious oil being caught in SOME cases, too.

If one is willing to experiment, and finds that it does indeed help with "ping" due to filtering out any oil getting into the combustion chamber via the old "PCV" path - that would be interesting.

I have mixed feelings on it - likely because of all the hype and claims out there from people who don't know engines and are listening to the cool guys who run them. But I've seen situations where it worked, too.

 

[ShadowsPapa]

i dont see that a catch can will do anything to reduce your rattle. its purpose is to catch blow by from going back into the intake.

Oil mist in the combustion chamber has been known to make detonation worse.

The thing here is - I can't hear this particular truck - is the detonation here problematic, or something that can be ignored?
I hate trying to fix over the internet when some of my senses are tied behind my back.

 

[iGlad]

Oil mist in the combustion chamber has been known to make detonation worse.

The thing here is - I can't hear this particular truck - is the detonation here problematic, or something that can be ignored?
I hate trying to fix over the internet when some of my senses are tied behind my back.

Ill try and get it on video later today to share in this thread and show the dealer as proof! lol

 

[flipmode]

Oil mist in the combustion chamber has been known to make detonation worse.

The thing here is - I can't hear this particular truck - is the detonation here problematic, or something that can be ignored?
I hate trying to fix over the internet when some of my senses are tied behind my back.

Haha, isn't that the kicker, trying to describe a sound with written word. I'm not sure that the detonation is problematic intrinsically, sometimes it just happens on occasion and I'm sure it varies among all the different engines of the world.

However, I don't really know much about the affects of detonation over years and years of driving, I'd like to keep my truck for a very long time. Seems like combustion happening outside the chamber can put a lot of added stress on head gaskets and other engine parts not designed to be exposed to it. If this engine is designed to handle detonations outside the combustion chamber, then no- I doubt its problematic. Detonation is inefficient, and causes additional stress. I'd like to think that engineers would like to reduce both of those things over the life of a product. Haha but what do I know?

If we're unable to determine that its not to be worried about, or that it can't be fixed, I can think of 392 cubic reasons to just replace the whole thing.

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