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My engine is knocking/pinging on 87/89 octane

BRuby

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Like all my vehicles I ran 87 in my 997.2. Ran just fine for the 7 years I owned It.
Yeah no one restricts any owner to put in any octane fuel they want
It will run - but why cheap out on something so fundamental
The manufacturer recommends for a reason

But especially under high load race track max performance
Best to use recommended high test - no ethanol when available
93 for ours always - still and always has run like brand new

To and from grocery work errands etc - 87 would get you there and back
But you do you
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stumblinhorse

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Yeah no one restricts any owner to put in any octane fuel they want
It will run - but why cheap out on something so fundamental
The manufacturer recommends for a reason

But especially under high load race track max performance
Best to use recommended high test - no ethanol when available
93 for ours always - still and always has run like brand new

To and from grocery work errands etc - 87 would get you there and back
But you do you
I didn’t “race” my 997, but I often spun the fan belt off and had to get it towed home to put it back together ;)

The word “required” is used with the 392. Not “recommended “
 

BRuby

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I didn’t “race” my 997, but I often spun the fan belt off and had to get it towed home to put it back together ;)

The word “required” is used with the 392. Not “recommended “
Our son ages ago learning the finer points of apex driving corners plus heel and toe at the track at age 18 or so. But insofar as required with the 392 - have never bothered to look what octane it uses - is req - or is rec. We have the V6.

Porsche we use though thrives on 92 or higher. So we always put in high test 93 no ethanol. Flat 6 screams fully pegged to rev limiter. Very fun - very tossable at high speeds. Handles like a dream.

Jeep Wrangler JL My engine is knocking/pinging on 87/89 octane 8253B4F2-A228-4B14-93C1-7F61CCC119F7
 
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AFD

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Kindly explain further— 91– 10% is the best standard pump gas available here and similar elsewhere. How can this be. If 93 was available in all states I would have the tune , except it could have been the factory tune. ??‍♂
My last car was an Evo X that I had shipped from California. It still required premium gas with an octane of 93 or higher for full performance, but allowed for 91 with reduced performance. I guess you could technically say that 93 is "recommended" instead of "required", but that's not how I understood it. More like a "Sure, it'll still work, but what other choice do you have?" type of thing.

I looked up the owner's manual, and this is exactly how it was worded..

Octane requirement
Your vehicle is designed to operate on premium grade unleaded gasoline having a minimum octane number of 93 [(MON+RON)/2] or higher for optimum performance. In case premium grade unleaded gasoline 93 is not available, unleaded gasoline rating of 91 can be used. However, the performance level is reduced. In order to maintain exhaust system durability, premium unleaded gasoline having an octane number of at least 91 must be used If the premium grade unleaded gasoline rating of 91 or higher is not available on journey, etc., regular unleaded gasoline having an octane number of 87 can be used temporarily as an emergency measure.
 

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2nd 392

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My last car was an Evo X that I had shipped from California. It still required premium gas with an octane of 93 or higher for full performance, but allowed for 91 with reduced performance. I guess you could technically say that 93 is "recommended" instead of "required", but that's not how I understood it. More like a "Sure, it'll still work, but what other choice do you have?" type of thing.

I looked up the owner's manual, and this is exactly how it was worded..
Old guy was raised with Words Mean Things , reinforced by the military and gets flabbergasted. IE- Requires did not mean suggested or recommended, Provide meant to make available not mandatory or must give . Add all the PC societal, woke, gender, bastardizing of the language. Sometimes I understand English as well as the two years of HS German very many moons ago.
 
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AFD

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Old guy was raised with Words Mean Things , reinforced by the military and gets flabbergasted. IE- Requires did not mean suggested or recommended, Provide meant to make available not mandatory or must give . Add all the PC societal, woke, gender, bastardizing of the language. Sometimes I understand English as well as the two years of HS German very many moons ago.
Your body doesn't necessarily require steak and meats to survive either, but I doubt most doctors would recommend that someone only eats fruits, veggies and soy every day ?‍♂

Semantics aside, for my last car, iirc the fuel cap and door specifically stated "unleaded premium required", with the manual basically stating 93 recommended with a minimum of 91 required (though I'm betting they would've said 93 required if that wouldn't have caused problems trying to sell the vehicle in markets without it). Kind of a read between the lines kinda thing for consumers I guess.
 

2nd 392

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Your body doesn't necessarily require steak and meats to survive either, but I doubt most doctors would recommend that someone only eats fruits, veggies and soy every day ?‍♂

Semantics aside, for my last car, iirc the fuel cap and door specifically stated "unleaded premium required", with the manual basically stating 93 recommended with a minimum of 91 required (though I'm betting they would've said 93 required if that wouldn't have caused problems trying to sell the vehicle in markets without it). Kind of a read between the lines kinda thing for consumers I guess.
My doctor doesn’t recommend steak, or anything else that tastes good, not “only” just mostly rabbit food, probably be happy if I went outside and “grazed”. …….. I don’t recall if there were many fuel recommendations in the way back days. My GTX did require 100 Octane I don’t know if it was in writing, common sense was common. When we lost it I couldn’t back the timing off far enough or pour enough fuel to it, even tried colder plugs out of desperation but still detonated. There are advantages to all the computers and sensors, this old guy being able to work on them is not one of them. If you can’t tune it with vacuum/feeler gauges ears, eyes and some trial and error I’m lost. My USAF knowledge was made Obsolete ~50 years ago when the radial engine aircraft were sent to the boneyard, and I’m still obsolete, hasn’t changed. But now I accept it, drink beer, and watch the more knowledgeable do the job. ?
 
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My 2022 3.6 with auto transmission pings and rattles going up hills or under load in the summer months. Has done this from day 1, I currently have 10,000 miles on it. Not a loud rattle, but you can hear it. If I let off the throttle it stops, definitely pinging. Dealer says they all do that and it is normal. I have never tried premium. Only does it when it is really hot outside and engine temps are above 215.
 

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BRuby

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Depends where in Canada I guess but due to all our new regulation requirements for fuel, there’s barley any ethanol free stations out here in BC. Chevron 94 is about all I can find now, even shell 93 here is 10% ethanol
Yep Chevron 94 is ethanol free
 

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My 2022 3.6 with auto transmission pings and rattles going up hills or under load in the summer months. Has done this from day 1, I currently have 10,000 miles on it. Not a loud rattle, but you can hear it. If I let off the throttle it stops, definitely pinging. Dealer says they all do that and it is normal. I have never tried premium. Only does it when it is really hot outside and engine temps are above 215.
Use 89 octane in it instead of 87 and your problem will be solved. They raised the compression when they redesigned the engine and really should've bumped the octane a bit to compensate. Sure it runs just fine on 87 but in circumstances like that it'll ping.
 
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My 2022 3.6 with auto transmission pings and rattles going up hills or under load in the summer months. Has done this from day 1, I currently have 10,000 miles on it. Not a loud rattle, but you can hear it. If I let off the throttle it stops, definitely pinging. Dealer says they all do that and it is normal. I have never tried premium. Only does it when it is really hot outside and engine temps are above 215.
"Dealer says they all do that and it is normal". yep typical of a dealer...
 

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When I run 87 octane or even 89 (up to the avg. of 15% ethanol), the motor pings and knocks at complete random RPM's, but absolutley ALWAYS does it when the engine is under a load. For example: it's a manual, so when im in first gear, go to about 9-10 mph, shift into 2nd gear, disengage the clutch and give it some throttle, its a pretty loud ping/knock that will last approximately 1 full second until torque has developed and there's no longer a stressful load on the engine. However, at any random time, no matter what gear or MPH, it will ping or knock. The only time it doesn't do this is when it is VERY cold (I live in PA), or when i am at highway speeds. There are absolutley no CEL's. The knock sensor isnt even picking it up. The motor is completely stock. 51,000 miles. I have OCD and change the oil every 3000 miles with AMSOIL 0-20 and a WIX filter. I always let this motor warm up to 120+ degrees before driving, and baby it until it reaches fully operating temperature (coolant and oil). Oil pressure is constant a 31 PSI. I have also did a smoke test to check for any vacuum leaks and could not find any. It also does not ping/knock when revved up in neutral or at idle.

I thought for the longest time that it was a loose nut/bolt rattling around the frame or engine bay, and i searched for a "rattle" (which is the only way to describe the sound if i didn't find out later it was in fact engine ping/knock), and i couldn't find shit. i looked under that engine and inside the frame holes and checked every single nut and bolt that was exposed enough for me to touch and made sure they were at the least finger tight and not moving around. i thought maybe the vibration in that specific RPM/throttle % zone would cause a vibration throughout the chassis/engine and it was just rattling a rock or nut or bolt or something.

Fast forward to July 4. The gas station chain (Sheetz) was selling gas, in any octane, for $1.776. I was 25 miles to empty, so i filled with 93 octane. i drove home (~2 miles) and motor was still pinging. Parked it and haven't drove it...

Until yesterday. Not only did I notice NO knocking/pinging whatsoever, the entire thing runs so much smoother. No matter what load i put on the engine, how low my rpm's were, how high the gear was, it NEVER knocked or pinged one time, and it was 91 degrees here.

Heres my questions:
1 - How do i fix this? I have an aftermarket warranty, but would they replace the engine or re-tune this?
2 - Before posting this I've read threads and people say this is common? and that FCA/Jeep said to just run 91+ and keep it above 2k RPM's? is this true? this vehicle is not REQUIRED to run 91+ octane, and i would imagine there would be a recall for an engine re-tune considering this cant be good for the motor?

I can try to post video of this noise, but my doors/top is off at the moment. I can link videos extremely similar to the noise it makes that i have found on youtube if that helps.
is the engine idling a bit rougher than when new by chance? Any progressive power loss over time?
 

azjl#3

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18 JL, 30k miles, 3.6, auto, 87 octane, drive under heavy load going up 7% inclines from 1,000 to 7,000 feet elevation, no ping. Ever. Did I mention it was 116 last week?
However, I do have 4.11 gearing?
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