Ping @ 3500 When Cold (stock)

CCS86

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Now that the weather is cooling off, something new has developed with my car. On cool mornings (< ~65*), before the car is fully warmed up, it will ping under heavy part throttle; always between 3400-3600 rpm. Just a quick clatter as it passes through that range. Running 93 octane from Shell.When fully hot, it clears up.

On the data log:

Coolant temp: 122
Spark Advance: 25
Commanded AFR: 14.8:1
Measured AFR: 15.3:1

It's running a little lean there, as my car tend to do. Most of the long term fuel trims are positive. But 15.3:1 is not excessively lean to knock at half throttle.

Thoughts?
 

jymboslice

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I'm guessing you are tuned? I would contact your tuner and ask him what is up with it.
 

CPRsm

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That's pretty lean. Even at half throttle, that rpm range is getting into peak cyl pressure where it's most likely to knock
 

CCS86

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That's pretty lean. Even at half throttle, that rpm range is getting into peak cyl pressure where it's most likely to knock


This computer seems to command a stoich AFR until you get deep into the pedal. 15.3:1 is only 4% lean, but I agree the cylinder pressures are pretty high there, even at half throttle.
 

CPRsm

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Yeah, stock takes 89% throttle before anything changes. Cams or AFR. maybe something lost in translation w ur guage.....I need to shoot for 14.0 here for stoich w E10. But I read in lambda. Will ur guage do that? Should be 1.0
 

CCS86

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Yeah, stock takes 89% throttle before anything changes. Cams or AFR. maybe something lost in translation w ur guage.....I need to shoot for 14.0 here for stoich w E10. But I read in lambda. Will ur guage do that? Should be 1.0


I'm logging with Torque Pro and a bluetooth dongle. Without a tuner I have no way to change target AFR's. Actually, none of the tuners let the end user change those tables without the high dollar add-on software right?
 

CPRsm

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I'm logging with Torque Pro and a bluetooth dongle. Without a tuner I have no way to change target AFR's. Actually, none of the tuners let the end user change those tables without the high dollar add-on software right?
yeah, not the tables for the end user. Just by percentage as a whole. But idk with this ECU. Can you log the knock sensors? Maybe pistok slap. Have you checked the plugs? Take it to the dealer And get it annotated in ur records if you have a problem later.
 

SicShelby09

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It's not pinging. It's noisey cam phasers before the oil gets all the way up there to quiet them down. Normal and most 5.0s do this. I had two 5.0s and they both did it. Completely normal. Don't sweat it.
 

SicShelby09

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And further more my first job one 5.0 did it bad until they flashed an updated stragety to it. There is a tsb on this.
 

halemach1

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Now that the weather is cooling off, something new has developed with my car. On cool mornings (< ~65*), before the car is fully warmed up, it will ping under heavy part throttle; always between 3400-3600 rpm. Just a quick clatter as it passes through that range. Running 93 octane from Shell.When fully hot, it clears up.

On the data log:

Coolant temp: 122
Spark Advance: 25
Commanded AFR: 14.8:1
Measured AFR: 15.3:1

It's running a little lean there, as my car tend to do. Most of the long term fuel trims are positive. But 15.3:1 is not excessively lean to knock at half throttle.

Thoughts?

:poke:
 

Bowtie-X

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Almost all cars these days command stoich at part throttle.


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CCS86

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It's not pinging. It's noisey cam phasers before the oil gets all the way up there to quiet them down. Normal and most 5.0s do this. I had two 5.0s and they both did it. Completely normal. Don't sweat it.



I don't agree at all. Full synthetic 5w-20 flows plenty well at 90*, and has been delivered to all corners of the engine within seconds of startup.

A noise like you're talking about doesn't remain quiet as rpms build, happen in a very small rpm window, clear up, then happen again at the same rpm in the next gear.




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CCS86

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On an unrelated note, I noticed a slapping sound at idle that I've never heard before. Isn't there a TSB for a stretched belt?

th_VIDEO0089.jpg
 

SicShelby09

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I don't agree at all. Full synthetic 5w-20 flows plenty well at 90*, and has been delivered to all corners of the engine within seconds of startup.

A noise like you're talking about doesn't remain quiet as rpms build, happen in a very small rpm window, clear up, then happen again at the same rpm in the next gear.




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You would be completely wrong. But hey, you came here asking for help. Oh well. I'll let you trouble shoot this to the moon. And when the dealer and everyone else tells you its normal, then maybe you will believe. Shit, head to the dealer and test drive a cold one. They will all do it. There are people here that work at dealers and drive these on a regular basis cold and have commented on how they do it normally. The cam phasers are at the top front of the valve covers and it takes the oil a little time to get up there.

Otherwise every GT I have been in, including two of my own were "pinging" from the factory....lol I guess you just figured out the #8 issue indirectly....LOLOL.
 

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