Throttle Delay Fix.

[SubieRumble]

I have searched and searched, but there doesn't seem to be too much information on fixing the slight delay between pushing in the gas pedal and the engine revving. Occasionally I find myself yearning for my old 240's instant response.

I have a K&N filter, Gruppe-s UEL header and the Openflash Tablet with OTS stage 2. Is there anything I could do to eliminate or lessen throttle delay?

Thanks.

[SubieRumble]

And yes, I am aware that there are limitations to throttle by wire but any additional insight is greatly appreciated.

[Ultramaroon]

Pedal dance. Cut the vehicle stability system out of the circuit. It's my pet peeve so I'm the guy that does it even in stop&go traffic.

[SubieRumble]

Does holding down the traction control button help? I tend to drive with the sport setting, but never really compared it to traction off.

[steve99]

VSC traction buttons only effect the stability control setting does not effect throttle response


log the tune make sure you ltft are fairly low at lower rpm like 5% or so also log when you jump on the throttle at lower rpm see if it bogs, you may need to either adjust load limits or lean out the low rpm/high load are of the ol fuel table


check your iam=1 and for any significant knock flkc or fbkc when you open throttle agressivly, knock correction and low iam will dull throttle response


as will running too rich

[Ultramaroon]

Originally Posted by SubieRumble

Does holding down the traction control button help? I tend to drive with the sport setting, but never really compared it to traction off.

No. Holding down traction control does not reduce the latency or whatever the hell it does. It still processes the accelerometer, wheel sensor, steering wheel position... all those inputs.

Pedal dance.

[Ultramaroon]

Originally Posted by steve99

VSC traction buttons only effect the stability control setting does not effect throttle response

I'd be keen on figuring out a way to prove (or disprove) it but I still swear that shit interferes with my right foot during normal operation.

[steve99]

Originally Posted by Ultramaroon

I'd be keen on figuring out a way to prove (or disprove) it but I still swear that shit interferes with my right foot during normal operation.

It will reduce throttle if loss of traction stability etc is detected. You can see it in logs if you log throttle pedal position vs throttle plate.


But im pretty sure it does not switch in a separate throttle map like in some subbies with the sport/sport sharp.


but yes to be 100% you would have to wade through the code.


ecutek do have features to remap throttle but this is extra ecutek racrom code not in stock code

[SubieRumble]

Thanks for all the replies. Looks like an E-Tune is in my future(not too keen on messing with tunes myself.)

[Ultramaroon]

Originally Posted by steve99

It will reduce throttle if loss of traction stability etc is detected. You can see it in logs if you log throttle pedal position vs throttle plate.


But im pretty sure it does not switch in a separate throttle map like in some subbies with the sport/sport sharp.


but yes to be 100% you would have to wade through the code.


ecutek do have features to remap throttle but this is extra ecutek racrom code not in stock code

It pulls throttle, or to be more accurate, feeds throttle more gradually if applied mid-turn. This is even before any loss-of-traction event is detected AND even if TCS is disabled via the button. I've picked out a specific corner and tested this enough to convince myself but I don't have hard numbers.

[EAGLE5]

Time for a standalone ECU!

[KoolBRZ]

Originally Posted by SubieRumble

I have searched and searched, but there doesn't seem to be too much information on fixing the slight delay between pushing in the gas pedal and the engine revving. Occasionally I find myself yearning for my old 240's instant response.

I have a K&N filter, Gruppe-s UEL header and the Openflash Tablet with OTS stage 2. Is there anything I could do to eliminate or lessen throttle delay?

Thanks.

The resident man of knowledge about these ECU's had this to tell me about the DBW tables;
"Well, the basics are 3 sets of tables - requested torque base, which is effectively a denominator that is used in conjunction with the requested torque A/B/C tables (which are different SI Drive modes) which feeds into the target throttle opening table.

In a nutshell, the requested torque at a specific RPM and accel pedal opening is divided by the relevant number in the base table to give you a ratio (e.g. 200 divided by 250 in the base table). This then gives you a ratio, that is the axis of the target throttle angle tables.

These tables can be tweaked for a more or less linear feel to the pedal - i.e. you can have it got WOT with very little pedal action (the stock approach) - which feels more 'peppy' but is less linear - or you can even it out to have a more 1 to 1 feel (i.e. 50% accel pedal equals 50% throttle). "

In my research about changing the DBW tables I found out that the ECU reads from right to left, so tables that have "filler" columns, (columns essentially the same as the column next to them) on the right side of the table will cause the ECU to react slower, than tables with the "filler" columns on the left side.

This is part of the reason there is a delay after throttle input. The solution, get a tune.

[EAGLE5]

Originally Posted by KoolBRZ

The resident man of knowledge about these ECU's had this to tell me about the DBW tables;
"Well, the basics are 3 sets of tables - requested torque base, which is effectively a denominator that is used in conjunction with the requested torque A/B/C tables (which are different SI Drive modes) which feeds into the target throttle opening table.

In a nutshell, the requested torque at a specific RPM and accel pedal opening is divided by the relevant number in the base table to give you a ratio (e.g. 200 divided by 250 in the base table). This then gives you a ratio, that is the axis of the target throttle angle tables.

These tables can be tweaked for a more or less linear feel to the pedal - i.e. you can have it got WOT with very little pedal action (the stock approach) - which feels more 'peppy' but is less linear - or you can even it out to have a more 1 to 1 feel (i.e. 50% accel pedal equals 50% throttle). "

In my research about changing the DBW tables I found out that the ECU reads from right to left, so tables that have "filler" columns, (columns essentially the same as the column next to them) on the right side of the table will cause the ECU to react slower, than tables with the "filler" columns on the left side.

This is part of the reason there is a delay after throttle input. The solution, get a tune.

Is that delay of reading columns measurable in logs?

[KoolBRZ]

Originally Posted by jsimon7777

Is that delay of reading columns measurable in logs?

It would be, if that was the only thing changed. But, since anyone who is modifying those tables would be changing a lot more, it's not really something that is done , if you know what I mean. The throttle could be made super-responsive, but it would be the cause of other problems. Drive-ability for one. There are also multiple types of delay. The delay from idle to acceleration is one. The delay from slow acceleration to fast is another. Which delay is bothering you the most?