Engine Knock at part throttle

[Courtsm3]

Quick overview. 20’ 3.6. AEV snorkel, dry filter and magnaflow crawler exhaust. No tune.
As of the last month or so Ive noticed some knock at part throttle, almost in the “light” throttle range. We just did a family trip towing my overland trailer about 5 hours and it was very evident. I thought it was bad gas but I’m now on my third tank, from different fill sites too. Still knock. Its quick, split second and then its gone. My wifes 3.6 Journey runs wayyyyy smoother. Curious who else has incurred this what they’ve done.

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[stil2low]

Some slight knock is common with the pentastar as it tries to trim the fuel to lean as much as it can. The knock sensors work quite well and will correct it
Trying to squeeze every bit of mpg they can out of it, it runs right along the edge of pre ignition lol

My last few JK’s and JL have all done the mid throttle rattle. If it get excessive, can try running a higher octane during the hot summer months. If that doesn’t clear it up and continues to get longer/louder then bring it in

 

[SelfmodJT]

Search rattle noise, plenty of threads on this. Its pre ignition or dentonation, if it does it on a hill and not on a decline thats what it is. I figure if it was something loose like the heatsheild it would make the noise reguardless of going up or down a hill.

 

[Courtsm3]

Yeah preignition. Its very brief. Im going to try 89 octane and see if it clears up

 

[ShadowsPapa]

Yeah preignition. Its very brief. Im going to try 89 octane and see if it clears up

Higher octane is for detonation. Preignition is different.
Preignition is when the charge is ignited before the spark (heat, etc.).
Detonation is when the charge is lit by the spark and the flame front pushes the unburned charge into a "corner" and the pressure and heat rise to the point it causes the fuel to self-ignite.

Mild detonation isn't uncommon nor normally destructive.
From your description - I'd totally ignore it - if it's so short and mild......

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