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I'm not sure if I'm getting proper values here, but my factory tune seems to have a lot of Knock Retard going on with the stock tune.
Attachment 130051
Log attached.
2019 Colorado 3.6 LGZ with 87 octane.
There's no ethanol or octane sensors on this truck, so I'm not sure if it's going off the high octane tables or low.
Every factory calibration is a little different, some show more KR than others. How the calibration deals with that is equally different from one platform to the next.
The ECU always starts at the high octane table after a cold start, and as KR is picked up, if it's over a certain threshold it starts moving away from the high octane timing table. You need to look at the knock adaptation calibration to determine what the threshold is for this to happen.
Keep in mind this engine is a high compression, high revving V6 that would probably really prefer to be operated on premium fuel. Hence, the knock strategy on this engine might look different than, say a V8, or a turbocharged 4 cylinder.
Yes quite normal.. Especially on GEN 5's.
And especially on 87 octane…!Quote:
Originally Posted by Alvin
Say I want to retain the ability to use 87 octane and keep the truck engine life as long as possible, should I start subtracting timing from the High Octane table (paste special, subtract)?Quote:
Originally Posted by tunerpro
Afterall, this is just an offroad lifted truck with a V6. I'm looking for driveability, economy, and longevity.
I've never actually heard a single knock/ping while driving it.
Look, try, do a test, take the tuning and lower the entire table by -6, go ride if you notice that it keeps giving KR and you don't hear it, you have a false KR, so what you should do is go to the knock sensor and see if it is well adjusted If it is not well adjusted, open your hptuners and raise a little sensitivity to the knock sensorQuote:
Originally Posted by Nanserbe
For reference, factory tune attached.
I know this has been discussed before, but for what it's worth knock will show if torque model is too low in these areas and if injection timing is too close to ignition timing. A lot of false knock happens for those reasons. Can still have sensitive sensors, but verify it's not real first.
Ah interesting! So does the ECM pull spark (in the form of knock) to limit torque in these areas?Quote:
Originally Posted by GHuggins
What's the best way to verify it's not false knock?
How do I know if it is well adjusted?Quote:
Originally Posted by Josue Galban
Completely normal, especially on 87 octane. The OEM logic registers knock and the potential for knock and then uses this info to add to the "Knock learn" value. Then the knock learn value is how much the spark advance leans towards the low octane table which will lower the total advance and reduce the knock retard values seen. If you run the car enough times you will see it automatically reduce spark advance and KR will drop.
Most GM cars shows knock even on 93. It's just part of their logic.
So is knock/ping on the Gen 5 engines okay to leave as is?
Or should I be chasing them down and reducing timing in those areas?
Quote:
Originally Posted by Nanserbe
As explained above its normal and you should leave it alone assuming your car is on the stock tune with stock parts.
Copy that, thank you!Quote:
Originally Posted by TriPinTaZ
And yes, stock parts and everything.