S_AUJP question

[ultm8z]

Does the S_AUJP xdf in TP cover every TPS scalar there is in the $8D code? For reference, I'm on v7.

Also for reference, my setup is a 383, mild cam, with a Miniram intake.

Reason I ask...

There's been this holy grail I've been chasing for a long long time in terms of throttle response and I've been dabbling in these online AI's about it the last few days. I'm a total ignoramus on the code and hex and all that stuff, but I do have the old ANHT hac file that I'm looking at.

One of these AI's is saying that there's some TPS sensitivity parameter in the 8D code where the ECM "waits" to determine whether the delta-voltage signal it received from the TPS is real or noise. This amounts to a few milliseconds or something depending on what this particular scalar value is set to.

That said, here's my situation...

There's a point right after a hot startup where the throttle response is razor sharp... I mean sharp-sharp-sharp...(some might call it "hair-trigger" sharp). It lasts for about 30-40 seconds and then you lose that. For example if I go to a store and then come back to the car... for about 40 seconds there's this absolutely phenomenal period of throttle response. After that time period, the response is still fantastic, but I can tell the difference. I.e., if someone got in my car and drove it around, they probably wouldn't notice the difference, but I do.

Its also not something i can detect in the TP data, since i captured the operation in that time period a few times trying to see what the difference was between that 40 seconds and everything after that.

I've always felt like it had something to do with the ECM's sensitivity to TPS changes, but I could never find a parameter that addressed it.

There is a scalar that deals with the delta-TPS threshold to activate TPS AE... the factory setting is 3.13% and I lowered it to the minimum .39% (at least what TP displays as the minimum). That made a HUGE difference with the Miniram. I've also played around with every AE delta-TPS and delta-MAP parameter there is in the v7 xdf...(tables, scalars, lag filters, etc) and I do have the throttle response dialed in very well.

But again, outside of that hot start, it always felt like there was just the tiniest bit of delay in the ECM responding to the TPS (like some sort of hidden lag filter or something). I also know it has to be TPS related and not MAP related because the time scale seems to be way too short.

I can envision the GM engineers putting some kind of delay in there to make the throttle not so much of a hair trigger for the average driver. But for me, I want that.

Any rate, hoping someone here knowledgeable about the code can let me know.

[ultm8z]

Also want to add that I'm 99.9999% sure it's not spark related...

I had thought that the ECM was doing something with spark timing during that 40 second window, but I've played around with adding and subtracting timing from every spark table I could find until the cows come home and still not able to replicate that 40 second window of throttle response.

[ultm8z]

I found a scalar

MAP Sensor Param, A/D Lag Filter Coefficient at location 6DC

There are references in the ANHT hac to getting the MAP sensor raw A/D, so the lag filter must be how the ECM reacts to that A/D value.

Since the ANHT hac mentions a TPS A/D, seems like it'd stand to reason that there'd be a lag filter coefficient associated with it?

[corvixa]

Intéressant ton retour ! Ça conforte l’idée qu’il y a forcément un filtre ou un délai côté TPS que GM a intégré, je me demande juste comment le fine-tuner sans tout casser.