Rattle from engine when accelerating (sounds like keys)

[ShadowsPapa]

You bought a truck for mpg?
My f250 got 12 mpg going up hill, down hill, head wind, tail wind, towing, not towing, loaded to the max, unloaded, pulling my car hauler, not pulling it - all 12 mpg.

Anything better than 14 on a truck makes me happy. I'd love more - better than the 20-21 it's been getting lately, but oh, well.

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[iGlad]

@ShadowsPapa Finally was able to get a somewhat decent video of the sound from within the truck.

 

[casualthursday]

This problem seems to be happening to a lot of people here on the Gladiator forums:

https://www.jeepgladiatorforum.com/forum/threads/engine-knock-at-part-throttle.46953/

https://www.jeepgladiatorforum.com/forum/threads/odd-engine-noise.37810/

And a very large number of people over on the JL Wrangler forum:

https://www.jlwranglerforums.com/forum/threads/rattling-upon-acceleration.10007/

 

[Deleted member 30519]

I was one of the first ones on the forum to report this but nobody knew anything at the time. The dealer blamed my track bar being loose which I knew was bs. I just got Yukon 5.13s installed and took a 3 hr trip home. The noise happened once or twice going through 2nd to 3rd as usually but it sounded little less loud and not as much vibration as it used to make.

 

[iGlad]

I have seen these as well but not many solutions from Jeep. @casualthursday


@Gladiator847 I am at 5.13s now as well. The sweet spot is always between 1500 - 2000 RPMs shifting from 3 to 4th or from 6 to 7th. Track bar being loose is a pretty sorry excuse..

 

[DAVECS1]

Replacing the cam, possibly the phazer, makes sense to me. I still think it is also software related and possibly a mechanical, software tolerance stack up.

The pre-ignition that I believe is happening based on my experience is the fuel is being consumed faster than intended, due to high cylinder pressure. The valves are closed longer than intended as the piston starts to travel upward. This creates a much higher cylinder pressure and hotter charge in the cylinder. Once the plug lights of the mix it is exploding faster and harder than intended, and the force is exerted on the piston before it has made full travel. Retarding timing will help, better fuel could help of it is not grossly off, or having the valves open and shut when needed, will help. The cam table does not look finished to me, but it xould also be due to how HPT presents the data.

 

[SelfmodJT]

Just out of curiosity, where do you guys hear the rattle noise coming from? Engine? Transmission? Exhaust area?

 

[Scrubb84]

I have seen these as well but not many solutions from Jeep. @casualthursday


@Gladiator847 I am at 5.13s now as well. The sweet spot is always between 1500 - 2000 RPMs shifting from 3 to 4th or from 6 to 7th. Track bar being loose is a pretty sorry excuse..

I think I got you beat, My local Jeep dealer blamed my detonation noise on ‘rocks in your tires’. Very heated discussion quickly followed.

 

[SelfmodJT]

I think I got you beat, My local Jeep dealer blamed my detonation noise on ‘rocks in your tires’. Very heated discussion quickly followed.

Lol, I think a way to prove that wrong would be to let them drive it cold before the oil temp reaches 180 or so. The engine is silent until the oil temp almost reaches normal operating temperature.

I was wondering, if detonation occurs only with load can you make it detonate if you apply the brake and step on the accelerator? Would that create enough load to produce the detonation? I have a manual so that would hard to do without feathering the clutch pretty bad.

 

[DAVECS1]

Lol, I think a way to prove that wrong would be to let them drive it cold before the oil temp reaches 180 or so. The engine is silent until the oil temp almost reaches normal operating temperature.

I was wondering, if detonation occurs only with load can you make it detonate if you apply the brake and step on the accelerator? Would that create enough load to produce the detonation? I have a manual so that would hard to do without feathering the clutch pretty bad.

This comment would lead me to believe tnhe phazer and oil weight with bad cam tuning os causing these issues.

 

[iGlad]

Lol, I think a way to prove that wrong would be to let them drive it cold before the oil temp reaches 180 or so. The engine is silent until the oil temp almost reaches normal operating temperature.

I was wondering, if detonation occurs only with load can you make it detonate if you apply the brake and step on the accelerator? Would that create enough load to produce the detonation? I have a manual so that would hard to do without feathering the clutch pretty bad.

I’ll try that in the morning.

 

[SelfmodJT]

I’ll try that in the morning.

Did you try it? Also, has anyone tried towing something with this issue?? Is the rattling noise any worse?

 

[SelfmodJT]

Just out of curiosity, is anyone having this rattle with a stock or near stock gladiator? By that I mean havent mod it to the point where they added a lot of additional weight. I wonder if the extra weight has anything to do with it? So I put in 93 octane for the first time and the jeep is quiet like the first time I drove it off the lot. I cant recall if the noise started when I added the winch, bumper, interior molle panels and the bed rack. So now what do I do? Put back 87 octane and have the rattle come back and tell the dealer to fix it or bite the bullet and pay an additional 1 dollar a gallon? What would you guys do?

 

[Higher_Ground]

I'm paying the extra $1/gal for gas right now.

I will go back to 87 at some point just to see if it's still a problem or worse. I don't have to drive far but I figure it's costing me ~$1/day right now to use 93.

My main issue was a series of unavoidable speed bumps. My route changed and I won't have to deal with those on a consistent basis anymore. I rarely heard anything outside of that specific scenario (repeated 6x daily).

I read the entire thread on the JL forum. Looks like a few over there have more severe knocking. They have a larger sample size than us and a longer time to deal with it. Lots of information but ultimately no closure... just avoiding low RPMs and using high octane gasoline. With an automatic (and traffic/speed limits) I can only control the latter.

 

[SelfmodJT]

I'm paying the extra $1/gal for gas right now.

I will go back to 87 at some point just to see if it's still a problem or worse. I don't have to drive far but I figure it's costing me ~$1/day right now to use 93.

My main issue was a series of unavoidable speed bumps. My route changed and I won't have to deal with those on a consistent basis anymore. I rarely heard anything outside of that specific scenario (repeated 6x daily).

I read the entire thread on the JL forum. Looks like a few over there have more severe knocking. They have a larger sample size than us and a longer time to deal with it. Lots of information but ultimately no closure... just avoiding low RPMs and using high octane gasoline. With an automatic (and traffic/speed limits) I can only control the latter.

What I dont understand is if the engine has detonation, why isnt the knock sensor correcting the issue???? Isnt that what it's for? If you have a bad knock sensor it will set off the check engine light, correct?

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