Engine Ping

[cassiri]

Has anyone else had noises at low rpm from the engine that sound like bad gas or timing causing pinging? It is not the normal racket that DFI motors create. It is a distinct pinging under light load when the motor is lugging.

The dealer can't hear it very well and said nothing turns up on fault codes. It is pretty consistent, I've just yet to spend enough time with them to demonstrate. Problem is, if it doesn't through a fault code, there is likely nothing they can do. It just doesn't seem right that the ignition control couldn't adjust for this.

 

[marctronixx]

get a stethoscope and listen to the engine and have someone rev the engine in spurts. best to do it when the motor is hot. this is what the techs use to listen.

also, what brand petrol are you using and do you use any additives? what octane?

here in cali they only have 91 which is unfortunate. there is a place that sells 100 octane which is awesome but its 10 dollars a gall. takes me 200 dollars to fill up but man o man does the car RUNNNNNNNNNNNNNNNNNNNNNNNN smooth!

I drive a constant speed 98% of the time (60 mph and on cruise) so I do not hear any ping.

one thing i have heard is a loud CLAK!! when the engine is hot but has been sitting for a while. you turn it over and you get that cam CLAK! sound--does it make sense what Im saying? that happens rare but I have heard it probably 5 times since I have had the car.


I was living in atlanta when i purchased the car and there is 93 and 94 octane there so i never heard this noise or any other noise. its only when i got out here to SOCAL and 91 octane did i begin to hear that CLAK! every once in a while.

 

[Dread_Parrot]

Octane

You could always try some octane boost ? You can get that at China-Mart or some Farm & Tractor supply store. Lucas oil makes some octane boost that is non-alcohol. Cassiri, buy some 92 or 93 octane gas and add octane boost. Shouldn't be any ping, unless its bogging down in 6th or seventh gear when trying to pull a hill.

Bummer Marc that you cannot get 92 or 93 octane in Kalifornia
I guess we're kinda lucky here in Virginia, we can get 93octane without ethanol.(If you can find the stations) pure-gas.org
I don't know what the 'clack' could be. Interesting. I will think about that.
Have a good one,
Parrott

 

[marctronixx]

CLACK is my way of trying to describe the sound. maybe its engine knock. it only happens when the engine room is hot on a hot day and after its only been shut off for a short time (run in to the store to grab something). it does not happen all the time, and is more rare than anything else. I just hear it and cringe. but i think it just knock on start up.

there IS 100 octane here. I put in 100 dollars worth of 76 100 octane and $9.99 a gallon. Bought me 10 gals. man the car LOVESSSSSSSSSSS that 100 octane. the acceleration and idle is super smooth................

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[ColoradoQX]

One other thing to keep in mind is that the V8 is a direct injection design. This sounds almost like a quieter version of a diesel at times.

Best,
Darrin

 

[cassiri]

I hear you on the octane. Having recently moved from a state with 92/3 octane to California, that could be part of the issue. Still I would expect the engine mgmt to adjust to avoid knocking.

I have tried an octane additive just last fill up to no avail. I almost always use Chevron both here and prior to the move.

I am willing to bet there is an engine mgmt flaw in there somewhere that does not properly adjust timing under certain circumstances.

The knock only happens in 2nd or mostly 3rd gear just after it shifts to that gear under light acceleration. So picture you are pulling away from the light and babying the throttle. Just as it shifts into 3rd you ease a bit more into the gas. The rpm's are only 1k and it will ping for a second or two until revs come up. You have to have the window down to hear it.

It will not happen in 1st gear or on the highway. My only consolation is that the engine is not throwing an error, but I'm still afraid long term it isn't good for the motor.

The short term solution is I have been driving more aggressively to avoid low rpms.

 

[marctronixx]

good post cassiri.

i use chevron exclusively. thank you for the follow up in regards to octane booster. i dont like using such products and your post convinced me i am on the right track.

i dont hear any ping, but i am not looking for it and i dont have my windows down (i never do), but again your post sheds light on things and I personally appreciate your opinion.

 

[Dread_Parrot]

ping

yeah I think you are correct Cassiri. Especially when you describe the ping occurring in 2nd and 3rd gear. Certainly not for a lack of RPM.
I haven't heard a ping, and I usually have the windows down in the summer. I feel lucky with no ping or accelerator vibration.
Parrott

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