Anyone hearing “pinging” on WOT?

[Krootz]

So I’m not sure if “pinging” is the right description, but I do hear something that sounds like that when I open it up. It sounds like sporadic “tinking” when I’ve got it to the floor.

I know that octane, gas quality, and cold/hot engine temps have an effect on this. I use Shell 93 octane religiously, but I’ve tried every brand and grade to see if it changed anything. The only changes I noticed were power delivery and MPG fluctuations from the different octane grades. Still has the subtle noises at WOT regardless of fuel grade/quality.

I am a car guy and have worked on quite a few engines over the years, but have never really had any experience with pinging or detonation (especially on newer computer controlled vehicles.) If I was to guess it sounds like the timing is the culprit, but this is a completely stock truck, as in paper air filter, stock exhaust, no mods whatsoever.

Anyone else hear this, is this just a quirk with all Hemis? Is this because the factory timing is dialed back so that it’s “safer” on the engine?

 

[2020Big4x4Horn]

Yes mine does this. I was wondering if I was the only one.

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[Krootz]

I keep seeing cracked manifolds being reported here, I hate to think that might be what I hear. I have zero experience with the sounds so I don’t know.

 

[rotts4u]

If you are running 93 already its unlikely its detonation. BUT if you want to be 100% sure get a tank of 93 and then add some octane booster on top of that and try again. If it still pings with 95-96 etc octane its gotta be something else other than detonation. Usually the knock sensors on the vehicle sense detonation and retard the spark timing a few degrees until it stops

 

[Krootz]

If you are running 93 already its unlikely its detonation. BUT if you want to be 100% sure get a tank of 93 and then add some octane booster on top of that and try again. If it still pings with 95-96 etc octane its gotta be something else other than detonation. Usually the knock sensors on the vehicle sense detonation and retard the spark timing a few degrees until it stops

Not a bad idea. I’ll try that and see what happens.

 

[MayhemMOORE]

Mine does it pretty consistently beginning at around 3K rpms, under any moderate load with decent throttle input. It is even more prevalent if towing something. I run 89 consistently and will switch to 91 for a few tanks sometimes and it still does it. I have never had a vehicle ping so much before and not pull timing to try to correct itself. I am waiting to have some extra time to be able to take it in to be looked at, as I also started hearing a loud tapping the other day under very light throttle just as you begin moving.

 

[JLaw297]

Yes. I first noticed this when I went from cruising around 45mph to 60-70% throttle to make a pass running 89 octane. I was able replicate it several times by doing the same thing and confirmed what I was hearing in the 3-5k rpm range. I tried a few different brands of 89, some better than others, but not fully gone until I filled up with 93. I initially thought it was a heat shield rattling or something until it didn't do it anymore with 93.

Interesting that the owners manual recommends 89 but we still get spark knock at that level. The knock sensors will pull timing to prevent it once knock is detected, but I've chosen to just continue running 93 from Costco (cheaper than local 89 in some cases).

 

[silver billet]

Definitely. The hemi pings pretty bad on 87 while working it. I use 89 or 91 while towing, but I've always managed to hear it ping a tiny bit under WOT regardless of octane.

 

[Krootz]

Yes. I first noticed this when I went from cruising around 45mph to 60-70% throttle to make a pass running 89 octane. I was able replicate it several times by doing the same thing and confirmed what I was hearing in the 3-5k rpm range. I tried a few different brands of 89, some better than others, but not fully gone until I filled up with 93. I initially thought it was a heat shield rattling or something until it didn't do it anymore with 93.

Interesting that the owners manual recommends 89 but we still get spark knock at that level. The knock sensors will pull timing to prevent it once knock is detected, but I've chosen to just continue running 93 from Costco (cheaper than local 89 in some cases).

Funny you mentioned Costco gas. I thought I tried all different brands and could have sworn I tried Costco 93 trying to hunt gas to eliminate the pinging.

I filled up with 93 at Costco this weekend and haven’t heard as much as a tap from the engine. She purrs and I’ve opened her up a few times since with no issues. Guess I’m fueling up at Costco from now on because Shell 93 made a damn racket in my hemi when I stood on it.

 

[2020Big4x4Horn]

Honestly I dont think the brands matter. There are fill terminals here. There's a citgo, bp, shell, Magellan, etc. And all the tanks trucks fill from whoever is cheapest that day no matter who they drive for because the driver gets a bonus.

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[Krootz]

I’m gonna use Costco premium only from now on and see if the pinging noises come back. If I hear it come back I’m gonna get it tuned and hopefully get the timing dialed in.

 

[iLikeTurtles]

I get belt chirp/squeak (like a tensioner is bad) under heavy acceleration. Sometimes I get loud tick like manifold but dealer declares it to be injectors.

 

[Scram1500]

I dump in a generous portion of Lucas fuel treatment every fill up and only use 93 octane from Mobil or Shell. I have never heard a ping once and I do like to stomp on it daily. I also have a catch can that keeps oil mist from the intake which is a potential source of pinging, probably why Demons run an oil separator from the factory

Fuel Treatment – Lucas Oil Products, Inc. – Keep That Engine Alive!

lucasoil.com

 

[Krootz]

Oil blow by into the intake causes pinging?!

 

[iLikeTurtles]

Oil blow by into the intake causes pinging?!

It enables incomplete combustion. “Ifso facto.”

Edit: my original logic was wrong. Is causes carbon deposits, altering minimally compression ratio therefore pinging

 

[brian42]

Honestly I dont think the brands matter. There are fill terminals here. There's a citgo, bp, shell, Magellan, etc. And all the tanks trucks fill from whoever is cheapest that day no matter who they drive for because the driver gets a bonus.

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True. Every station gets their gas from the same distribution center in the area. It's the additive package that makes it Mobil, Shell, Chevron, etc.

As long as it's a Top Tier station I'll fill up there. It just so happens that Costco is the cheapest least expensive around. 91 octane there is about the same as 89 octane at Top Tier stations around me.

 

[MannymanX]

Mine does since day one.
Switched to Costco 91 about two months ago(After 38K miles) and it helped a lot...
Kinda sucks that i need to use higher octane than required.

 

[jjhall8]

I run 87 and no pinging

 

[Krootz]

I run 87 and no pinging

Do you run a catch can by chance?

 

[jjhall8]

Do you run a catch can by chance?

Yes, first thing I did. Was installed with 50 miles on truck. 15.5 mpg with no highway miles. 700 miles on truck 2021 Rebel.