2013 5.0 Negative knock sensor

[cb900f]

Hello!

Datalogging with LiveLink and I'm seeing about 2 degrees of negative Knock Sensor. Does this mean it's adding timing? If so, how does it decide? IAT?

:beer:

 

[Joey8]

Believe its adding timing. Positive knock is what you want to keep an eye out for as it pulls timing. Regardless sub'd to learn about this.

 

[cb900f]

I did some more "Googling" and I agree. Negative does seem to be adding timing. But does anyone know how it decides to do this??

 

[Joey8]

The computer in the car is constantly monitoring a bunch of parameters. If it senses knock it will pull timing. If it doesn't i'm assuming it will advance timing. This is all based on your tune to.

 

[VNMOUS1]

Yes, it's advancing spark. If the KS doesn't hear anything and everything else is in line (heat, load, a/f from the onboard widebands, etc) it will add timing til it senses knock. Nice, huh?

 

[cb900f]

Yes, it's advancing spark. If the KS doesn't hear anything and everything else is in line (heat, load, a/f from the onboard widebands, etc) it will add timing til it senses knock. Nice, huh?

Maybe. I'm running a boosted setup on a stock motor. Is that still recommended?

 

[VNMOUS1]

Maybe. I'm running a boosted setup on a stock motor. Is that still recommended?

Like a VMP TVS 2.3L for Coyote? (If not, why not?!)

The cal still does the same thing. BUT, some of the values that it looks at to determine whether it can still add spark may have changed based on your calibration provided with the blower or by your local tuner. Safe? Yeah, probably unless something was really out of bounds. Doubtful.

bj

 

[JUIC3D]

How the car is tuned will determine the amount of timing, if any, the knock sensor will allow the computer to add and also the amount it will retard and the rate at which it will retard. It's not a cut and dry "oh the knock sensor will add timing until it sees knock" response. It's all in how the car is tuned.

 

[VNMOUS1]

Yes, it's advancing spark. If the KS doesn't hear anything and everything else is in line (heat, load, a/f from the onboard widebands, etc) it will add timing til it senses knock. Nice, huh?

How the car is tuned will determine the amount of timing, if any, the knock sensor will allow the computer to add and also the amount it will retard and the rate at which it will retard. It's not a cut and dry "oh the knock sensor will add timing until it sees knock" response. It's all in how the car is tuned.

If the above quote is what you're referencing, it's an apples to apples comparison. Yes you can change the table in the tune to not add anything. But again, if it's an apples to apples comparison and everything else is in line (note the few examples in parens) it's going to add as much as possible, per the tables, until it hears knock.

bj