Help with random false knock at part throttle?

[pmor4243]

I'm hoping to get some thoughts on tracking down the cause of some false knock that I have been getting. I've read through a lot of threads and checked all of the typically recommended areas and have not had any luck pinpointing where this would be coming from. Ran a tank of 100 octane race fuel through with no change. Did a compressions test and all cylinders checked out fine.

I attached a log to showcase this but this happens completely randomly. The only thing that is consistent is that it will occur at partial throttle in 1-3rd gear from a stop, outside of that, no problems. When it does happen, the knock values will pretty much immediately max out at +9.9 and seem to stay pretty high until I let off the throttle. Once I let off, knock values drop and don’t come back until the next random occurrence.

As you can see in the log, I happened to catch it live when driving around and replicated the same conditions back to back and was not able to reproduce it which has been the issue now for a while. It seems like on each drive Ill see my SCT displaying a maxed out knock value that occurs at some random point coming off a stoplight.

Does anyone have any thoughts or ideas on what to check here, or should I just chalk it up to a characteristic of the car at this point?

As far as the vehicle, it is a 19 GT PP1 10 speed with a Procharger P1X tuned by Wengerd

Datazap Log of Knock occurrence: https://datazap.me/u/pmor4243/part-throttle-knock?log=0&data=17-29

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[pmor4243]

Just following up in case anyone has any feedback. After looking over the logs some more, I was able to recreate the condition today a few times.

It appears to only happen at very light throttle coming from a stop in 1st gear. Even knowing that and trying to reproduce it, it is still fairly random as to when it occurs, but when it does, the knock sensor jumps to 9 almost immediately.

I wouldn't really worry about it too much but what sucks is that when it does happen, the car will continue to pull timing pretty much until I let off, which 9* of timing being pulled is definitely noticeable. That said, it is a street car and I can be OK with the fact that sometimes, once in a while the car will just be a little slower than other times.

Can anyone think of an underlying problem either mechanical or tune related that may cause this behavior? At the end of the day, is the car registering knock like that at such low throttle input and load anything to worry about?

 

[Jackson1320]

If there is not enough oil pressure the chains can start rattling. Are you lugging the car when it happens?

 

[pmor4243]

If there is not enough oil pressure the chains can start rattling. Are you lugging the car when it happens?

No, cant say that I am lugging the car at all actually. Just light throttle in first gear from a stop, pretty normal stop and go type driving behavior.

 

[DougS550]

No, cant say that I am lugging the car at all actually. Just light throttle in first gear from a stop, pretty normal stop and go type driving behavior.

Just wondering, what LTH are you running?

 

[pmor4243]

Just wondering, what LTH are you running?

Headers are still stock.

 

[pmor4243]

So maybe a better question on this may be, could this actually be real knock?

Given that it happens so randomly, is there a chance that for some reason at that very light throttle tip in from a stop, that once in a while the car does actually detect a knock event large enough to max out, even with 100 octane fuel? But then essentially be knock free in just about every other situation.

Seems very unlikely to me but I'm open to the possibility that the sensor are actually doing their job

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