Noisy lifters - LS3 - cold start.

[426Cuda]

Only certain parts of the tune are affected by in gear or park neutral. The main thing here is that it happens while ECT is below operating.

Yeah, I thought that might be the case. Strange no one else on here has this sound. Or, maybe they do?

 

[monstar]

I'd say it is on all with that OS version in the ECU, which is same since HSV 340 in 2013.

 

[Ron Burgundy]

And if you gently rev it as your rolling along in neutral? No strange noise?

Exactly....

 

[monstar]

When you let off throttle almost completely like just touching before shift occurs does it disappear for the moment car is changing gears?

 

[Ron Burgundy]

When you let off throttle almost completely like just touching before shift occurs does it disappear for the moment car is changing gears?

Yes. Thats exactly what happens. Goes away when i start backing of the throttle and is quiet when between gears

 

[monstar]

Yes. Thats exactly what happens. Goes away when i start backing of the throttle and is quiet when between gears

Well then, ta dah!!! it's a form of light burst knock, totally planned, totally under control.
You can tune it out but I wouldn't, neither will Holden.

 

[426Cuda]

Your a wizard, no doubt.
For my knowledge. Light burst knock? So fuel mix (AFR) is rich, timing advanced? But why would they program in knock? I would have thought the processor would be pulling timing out to reduce it? Or are you saying it's an accepted level of knock under light load only, with more timing used to have the motor preform better under cold, light throttle conditions?

 

[07GTS]

burst knock is predicted knock not actual knock, its just thinking under the conditions with what all the sensors say there could be potential knock so it takes a predetermined amount of spark out for a set crank deg count ect, for example i have mine almost removed because of the blower when it sees the rush of air it freaks out and takes timing out, it shouldnt be there under light load conditions tho

 

[monstar]

burst knock is predicted knock not actual knock, its just thinking under the conditions with what all the sensors say there could be potential knock so it takes a predetermined amount of spark out for a set crank deg count ect, for example i have mine almost removed because of the blower when it sees the rush of air it freaks out and takes timing out, it shouldnt be there under light load conditions tho

Explaining how retard when cold for cat light off, and cold engine noise reduction is brought back to normal offset by tricky transient mechanism deliberately advancing under startup load called launch spark.
This in turn is kept in line whilst cold with (burst?) retard shifting gears.
Like I said earlier you can zero all this tricky emissions and noise stuff out but once you know what it is and that's not car dying slowly coz pistons slapping and rocking, you can live with it. Else soundproof the bay.

 

[Ron Burgundy]

Explaining how retard when cold for cat light off, and cold engine noise reduction is brought back to normal offset by tricky transient mechanism deliberately advancing under startup load called launch spark.
This in turn is kept in line whilst cold with (burst?) retard shifting gears.
Like I said earlier you can zero all this tricky emissions and noise stuff out but once you know what it is and that's not car dying slowly coz pistons slapping and rocking, you can live with it. Else soundproof the bay.

You seem like you know what you are talking about mate. Your explanation seems logically sound...I will take your word for it ... thanks bruz