Pinging noise... I think

[07Burb]

Yes you guys are definitely experiencing pinging (pre-detontation). Which engine, brand of gas/octane, aftermarket intake, and tune do you guys have?

Edgar I know you mentioned using 91 octane. Do you have the 5.3L with AFM?

I thought this was the case too until Edgar mentioned putting in 91 octane. I experienced similar issues until i started putting higher octane into mine and it went away

 

[Zed 71]

There are a few factors (A/F ratio, spark plug gaps, MAF, etc.) that can affect pre-detontation even though 91 octane is being used. I find that cheap gas (even though it is rated at 91 octane) does not perform well in my sports coupe. Even if it seems to work well initially, long term use may lead to unwanted deposits.

In any case, once the basics are confirmed it will help with troubleshooting.

 

[KMeloney]

I always thought that detonation occurred under high RPM conditions. My noise occurred under low(er) RPM conditions. Does it not matter what the RPM range is?

It would make sense that my noise largely went away after I removed the BB tune before heading to the dealership.

I'm in PA, and run 87 octane gas (as that's what two different service managers said I should be using)...

 

[Zed 71]

Pre-detonation can occur at any rpm range (even idling, severe case); however, it is mostly observed after modifications/issues affecting the A/F ratio, timing, etc.

Your BB tune may be too agressive for your conditions (perhaps grade of gas), and Justin can dial it back a bit. I would log a session that mimics these conditions and send to Justin to adjust the tune. If I remember correctly, you were evaluating the differences between the aftermarket CAI and stock. Assess the pinging conditions with those changes and which tune was on the truck. Curious to see if there is some correlation: high A/F with agressive tune.

 

[AZSCTACO]

I'm gonna say a long shot and say the fuel pump is starting to go bad. Mine went bad at 80K miles and I heard some pinging on acceleration from time to time.

 

[puckhead]

I'm gonna say a long shot and say the fuel pump is starting to go bad. Mine went bad at 80K miles and I heard some pinging on acceleration from time to time.

Thought that was it with mine for a while put I replaced the bump and everything.

If anyone elses is like mine it is definitely in the engine. Guess it is pinging. I use mid grade with BBtune and intake.

So what is "good gas" and where can we get it?

 

[edgaranah1]

My engine is all stock. I dont have a tune/CAI or anything for that matter. and I just noticed today as I was going up a hill its def worse. I have always used 91 octane from shell. I just moved recently and dont fill up at the same gas station. U guys think that has something to do?


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[Zed 71]

Andy, IMO good gas is the stuff from Chevron or Shell. I have never had a problem with my sports coupe (which is really picky), and it has good additives for keeping injectors and cylinder walls relatively clean.

Edgar, since you are completely stock and under warrenty (assuming you are less than 100k), I would bring it in to the dealer. Also assuming all the basic maintenance is up to date.

Alex, you are correct that a fuel pump that is not providing enough fuel is one of the factors that can create a lean condition (high A/F) which can lead to pre-detotonation.

 

[puckhead]

Andy, IMO good gas is the stuff from Chevron or Shell. I have never had a problem with my sports coupe (which is really picky), and it has good additives for keeping injectors and cylinder walls relatively clean.

Edgar, since you are completely stock and under warrenty (assuming you are less than 100k), I would bring it in to the dealer. Also assuming all the basic maintenance is up to date.

Alex, you are correct that a fuel pump that is not providing enough fuel is one of the factors that can create a lean condition (high A/F) which can lead to pre-detotonation.

Thanks bud! I will have to look around and see what we have. I dont know as if there are shell or chevron stations around me. Do they supply to other stations?

 

[07Burb]

I usually get my gas at Quiktrip and have good luck most of the time. If I get 89 or greater octane gas I'm usually pretty good but sometimes we still get the pinging on 89 octane.

I may bite the bullet and change the spark plugs soon just to see what difference it makes. It's about time for that anyway