Anyone play with the throttle cracker settings?

[SloppyRob]

In Neutral (manual) I have no problems what so ever. The idle is rock steady. The only problem is when the rpm's are up to like 3k and I stop short. This is where the dip occurs. I dunno if it is even a problem as I don't remember if my car did this with the stock cam in there. Another situation is just reving at idle. I was trying to have the revs come down and stop perfectly at 800 rpms. Mine dips slightly below and bounces back to 800. Again im not sure if the stock cam does this as well.

The more I played with the decay values the worse of a surge on the comeback (back up to 800rpm) I got.

Also my IAC count at idle is around 80-90 fully warmed up.

I dunno I think Im gonna leave it as is and start tuning the part throttle and Wot stuff.

Oh, by the way I forgot to add that when I had the decay vals maxed at 0 for 0-10mph I noticed with the scanner that the timing remained fixed at like 22*. Usually the car bounces around from 18-24 at idle. It was strange and also the idle didn't feel as smooth.

[Torch]

what about drilling the TB hole so the iac won't have to react in such large swings?

I had the same problem when I installed my crappy BBK 80mm TB. When I drilled the TB just like the stock TB, my problems went away. I didn't have the ability to tune at the time so this was my only option. Typically the IAC count at idle should be between 30-50 and under load <120. I'm hoping the next scanner upgrade to VCM includes monitoring the IAC count.

[SloppyRob]

VCM scanner shows IAC count. Thats how i got those numbers!

I think under load the IAC is like 180 or so!

I really don't wann drill the tb but it sounds like this is my solution. I'll wait a bit and try some different things.

[mrkrad]

so for a 112lsa/cammed car what would be ideal IAC at startup,idle, and in gear (auto). Anyone know? That way i can figure out how to go about my target.

also my base TPS V is cracked open to .5v, if i were to turn the screw more to open up the TB plate a little more at idle would that do the same as the tb hole drilling?

[SloppyRob]

Yes adjusting the idle screw will give similar results as drilling the tb.

I don't know about the IAC question as my car is a manual.

[jimmyblue]

If you crack the throttle by the stop screw however,
too far will take you out of the idle cells and into the
"normal" ones if your TPS voltage comes up too much.
Whether that's a problem for you, I couldn't say.

[mrkrad]

is .5V normal idle stop ?

[Torch]

VCM scanner shows IAC count. Thats how i got those numbers!

I think under load the IAC is like 180 or so!

I really don't wann drill the tb but it sounds like this is my solution. I'll wait a bit and try some different things.

My scanner only has IAT (Import Air Temp). This must be a feature in the upgraded scanner.

[SloppyRob]

Ok, I went back to playing around and decided (I think everybody else told me this) that the VE table and throttle follower would solve my problems....So I scaled the VE table an additional .95 from 400-1200rpms (previously scaled .60, .80, .90) and scaled the 0mph-10mph throttle follower decay in Neutral only by .90 and what do you know......my car idles near perfect and the stopping dips have eased to the point where they are barely noticable! I could try and adjust the follower a little more but I figure I'll give the car some time to adjust and see how it goes!

So to anyone who has the rpm dip/surge when stopping the key is a combo of VE tables and throttle follower decay in neutral!

P.S. This software Rocks

[mrkrad]

sloppy would you mind posting your actual #'s changed.

[mrkrad]

Anyhoo i got a perfect 700rpm idle (112lsa A4), but my idle is still about 900-1000 (seems to idle higher than requested, is this cause i drilled the hole?) In gear i am still noticing a surge till full op temps.

Say if i in gear, reverse/D, with brake on the car will do
the ole

1100->900->1200->800->1300->700->1400->600->die
swoop. Doesn't occur after randomly copying a 231/237 tuned car. I didn't play with timing at 700rpm out of gear im at 10-11timing, at 900-1000rpm in gear im sweeping.

My previous training taught me that timing and moving idle's had alot to do. a degree or two could bump the timing, a slope of 10degrees to 20 could cause a major pendulum effect. Anyone car to copy your timing array and post the printscreen? I can host it Just wanna see what the low idle timing should be for perfect drivability and no pendulum of death.

hptuners rox

[SloppyRob]

MrKrad,
Im at work so i don't have access to the actual decay values but i scaled these by .95 from 0-10mph in park/neutral because i was having problems when shifting to neutral and slowing down for stop signs etc. Unfortunately the tune worked on one day but the weather is constantly changing here in NY and has had a definite effect on my in/out of gear idle characteristics. I haven't drilled the tb any but may have to as i've never seen my IAC count below like 74. My idle is at 800 on my m6 Z and is near rock steady when sitting still as the chart is flatlined for my idle. I may have to try adding or removing by degree some timing to avoid slight surges. Also I do have some bucking at really low rpms and barely on the throttle in gear. Im thinking that this can be tuned when i modify the maf table for cruise which i have yet to do.

[mrkrad]

here's whats going on while therse some driveline lash in 3rd gear lockup. Any tips?
[pre]

Engine RPM ,Vehicle Speed mph,IAC Steps ,Throttle Position % %,Ignition Timing Advance ,IAC Desired Steps ,Idle Airflow Desired g/sec
Mass Air Flow lb/min,Manifold Absolute Pressure psi,Engine Coolant Temperature °F,Intake Air Temperature °F,INJ. Pulse Width Avg. Bank 1 ms,
INJ. Pulse Width Avg. Bank 2 ms, Short Term Fuel Trim Bank 1 %,Short Term Fuel Trim Bank 2 %,Long Term Fuel Trim Bank 1 %,Long Term Fuel Trim Bank 2 %
Fuel Trim Cell ,

1509,31,98.0,0,38.5,98,8.68,1.75,5.5,188,129,3.1,3 .1,-12.5,-10.2,-1.6,-3.9,4,
1516,32,98.0,0,39.0,98,8.66,1.75,5.5,188,129,3.1,3 .1,-11.7,-9.4,-1.6,-3.9,4,
1545,32,98.0,0,39.0,98,8.68,1.75,5.5,188,129,3.0,3 .0,-11.7,-7.8,-1.6,-3.9,4,
1507,32,99.0,0,38.5,98,8.68,1.74,5.5,188,129,3.1,3 .1,-10.2,-6.2,-1.6,-3.9,4,
1549,33,98.0,0,39.5,98,8.67,1.74,5.5,188,129,3.1,3 .1,-8.6,-4.7,-1.6,-3.9,4,
1544,32,99.0,0,38.5,98,8.70,1.76,5.5,188,129,3.2,3 .2,-7.0,-2.3,-1.6,-3.9,4,
1526,33,98.0,0,40.0,98,8.68,1.73,5.5,188,129,3.3,3 .3,-4.7,-1.6,-1.6,-3.9,4,
1579,32,99.0,0,39.0,98,8.71,1.73,5.4,188,127,3.2,3 .3,-3.9,0.0,-1.6,-3.9,4,
1538,33,98.0,0,39.5,98,8.69,1.71,5.5,188,127,3.3,3 .4,-3.1,-9.4,-1.6,-3.9,4,
1587,33,99.0,0,39.5,98,8.70,1.75,5.4,188,127,3.3,3 .0,-12.5,-8.6,-1.6,-4.7,4,
1561,33,99.0,0,39.5,98,8.71,1.72,5.4,188,127,3.0,3 .0,-10.2,-9.4,-1.6,-4.7,4,
1578,33,99.0,0,39.5,98,8.71,1.74,5.4,188,127,3.0,3 .0,-10.2,-9.4,-1.6,-4.7,4,
1573,34,99.0,0,40.0,98,8.71,1.73,5.4,188,127,3.0,2 .9,-10.9,-10.2,-3.1,-4.7,4,
1574,34,99.0,0,40.0,98,8.72,1.74,5.4,188,127,2.9,2 .9,-11.7,-11.7,-2.3,-4.7,4,
1585,34,99.0,0,40.0,98,8.71,1.74,5.4,188,127,2.7,2 .6,-13.3,-12.5,-2.3,-5.5,4,
1581,34,99.0,0,40.0,98,8.72,1.73,5.4,188,127,2.8,2 .8,-14.1,-13.3,-2.3,-5.5,4,
1605,34,99.0,0,40.5,98,8.72,1.74,5.4,188,127,2.8,2 .7,-14.8,-7.0,-2.3,-5.5,4,
1611,34,99.0,0,40.5,98,8.73,1.74,5.4,188,127,2.9,2 .9,-8.6,-7.0,-2.3,-5.5,4,
1592,34,99.0,0,40.0,98,8.74,1.74,5.2,188,127,2.9,2 .9,-8.6,-6.2,-2.3,-5.5,4,
1594,34,99.0,0,40.5,98,8.73,1.74,5.4,188,127,2.9,2 .9,-7.8,-5.5,-2.3,-5.5,4,
1643,34,99.0,0,40.5,98,8.74,1.74,5.2,188,127,3.0,2 .9,-7.0,-3.9,-2.3,-5.5,4,
1598,34,99.0,0,40.0,98,8.75,1.76,5.2,188,127,2.9,2 .9,-6.2,-3.1,-2.3,-5.5,4,
1638,35,99.0,0,40.5,98,8.74,1.75,5.2,186,127,2.9,2 .9,-4.7,-0.8,-2.3,-5.5,4,
1635,34,99.0,0,40.5,98,8.75,1.72,5.2,186,127,2.9,2 .9,-3.1,0.8,-2.3,-5.5,4,
1614,34,99.0,0,40.5,98,8.75,1.72,5.2,186,127,2.9,3 .0,-1.6,1.6,-2.3,-5.5,4,
1635,34,99.0,0,40.5,98,8.74,1.76,5.2,186,127,3.0,3 .0,-0.8,3.1,-2.3,-5.5,4,
1651,35,99.0,0,40.5,100,8.75,1.77,5.1,186,127,2.9, 3.0,0.8,3.9,-2.3,-5.5,4,
1631,35,100.0,0,40.5,98,8.76,1.75,5.1,186,125,2.9, 2.9,1.6,5.5,-2.3,-5.5,4,
1644,35,99.0,0,40.5,98,8.75,1.74,5.1,186,125,3.0,3 .1,2.4,6.3,-2.3,-5.5,4,
1660,35,99.0,0,40.5,98,8.76,1.77,5.1,186,125,3.0,3 .0,3.9,7.8,-2.3,-5.5,4,
1652,35,99.0,0,40.5,98,8.76,1.72,5.1,186,125,3.0,3 .0,4.7,-2.3,-2.3,-5.5,4,
1655,35,99.0,0,40.5,98,8.76,1.76,5.1,186,125,2.9,2 .7,5.5,0.0,-2.3,-5.5,4,
1652,35,99.0,0,40.5,98,8.76,1.76,5.1,186,125,2.9,2 .7,7.0,0.0,-2.3,-5.5,4,
1640,36,99.0,0,40.5,98,8.76,1.78,5.1,186,125,3.0,2 .8,-1.6,0.0,-2.3,-5.5,4,
1675,36,99.0,0,40.5,98,8.76,1.77,5.1,186,125,2.8,2 .8,5.5,4.7,-2.3,-5.5,4,
1663,36,99.0,0,40.5,98,8.77,1.77,5.1,186,125,2.8,2 .8,5.5,5.5,-2.3,-5.5,4,
1648,36,99.0,0,40.5,98,8.77,1.76,5.1,186,125,3.0,2 .9,7.0,6.3,-2.3,-5.5,4,
1680,36,99.0,0,40.5,98,8.76,1.74,5.1,186,123,2.9,2 .8,7.8,7.0,-2.3,-5.5,4,
1648,35,99.0,0,40.5,98,8.77,1.73,5.1,186,123,3.1,2 .9,9.4,7.8,-2.3,-5.5,4,
1664,36,99.0,0,40.5,98,8.76,1.74,5.1,186,123,3.1,3 .0,10.2,9.4,-1.6,-5.5,4,
1704,36,99.0,0,40.5,98,8.77,1.76,4.9,186,123,3.1,3 .0,11.7,11.7,-1.6,-5.5,4,
1666,36,99.0,0,40.5,98,8.78,1.77,4.9,186,123,3.0,2 .9,12.5,12.5,-1.6,-4.7,4,
1658,36,99.0,0,40.5,98,8.77,1.75,4.9,186,123,3.2,3 .1,4.7,14.1,-1.6,-4.7,4,
1696,35,99.0,0,40.5,98,8.77,1.74,4.9,186,123,3.0,3 .1,5.5,15.6,-1.6,-4.7,4,
1677,36,99.0,0,40.5,98,8.77,1.73,4.9,186,123,2.9,3 .0,4.7,5.5,-1.6,-4.7,4,
1652,36,99.0,0,40.5,98,8.77,1.77,4.9,186,123,2.9,2 .9,4.7,7.0,-1.6,-4.7,4,
1682,36,99.0,0,40.5,98,8.76,1.77,4.9,186,123,2.9,2 .9,3.9,7.0,-1.6,-4.7,4,
1712,36,99.0,0,40.5,98,8.77,1.78,4.9,186,121,2.9,2 .9,3.1,6.3,-1.6,-4.7,4,
1675,36,99.0,0,40.5,98,8.78,1.77,4.9,186,121,2.9,2 .9,2.4,5.5,-1.6,-4.7,4,
1687,36,99.0,0,40.5,98,8.77,1.73,4.9,186,121,2.9,2 .9,1.6,4.7,-1.6,-4.7,4,
1698,36,99.0,0,40.5,98,8.77,1.76,4.9,186,121,2.8,2 .8,7.0,3.9,-1.6,-4.7,4,
1684,36,99.0,0,40.5,98,8.77,1.76,4.9,186,121,2.9,2 .8,7.0,3.9,-1.6,-4.7,4,
1695,36,99.0,0,40.5,98,8.77,1.74,4.9,186,121,2.9,2 .9,7.8,9.4,-1.6,-4.7,4,
1677,36,99.0,0,40.5,98,8.77,1.78,4.9,186,121,3.0,2 .9,7.8,9.4,-0.8,-4.7,4,
1682,36,99.0,0,40.5,98,8.77,1.77,4.9,186,121,3.0,2 .9,8.6,10.2,-0.8,-3.9,4,
1688,36,99.0,0,40.5,98,8.77,1.76,4.9,186,121,3.0,3 .0,9.4,10.9,-0.8,-3.9,4,
1695,36,99.0,0,40.5,98,8.77,1.78,4.9,186,121,3.0,2 .9,10.9,5.5,-0.8,-3.9,4,
1691,36,99.0,0,40.5,98,8.77,1.77,4.9,186,121,3.1,2 .9,4.7,4.7,0.0,-3.9,4,
1679,36,99.0,0,40.5,98,8.77,1.74,4.9,186,121,2.9,2 .9,4.7,3.9,0.0,-3.9,4,
1686,36,99.0,0,40.5,98,8.77,1.75,4.9,186,121,2.9,2 .9,3.9,3.9,0.0,-3.9,4,
1694,36,99.0,0,40.5,98,8.77,1.81,4.9,186,121,2.9,2 .8,3.9,3.1,0.0,-3.9,4,
1696,36,99.0,0,40.5,98,8.77,1.75,4.9,186,121,2.9,2 .8,3.1,1.6,0.0,-3.9,4,
1700,36,99.0,0,40.5,98,8.77,1.76,4.9,186,120,2.9,2 .8,2.4,0.0,0.0,-3.9,4,
1679,36,99.0,0,40.5,98,8.77,1.77,4.9,186,120,2.9,2 .7,0.8,0.0,0.0,-3.9,4,
1678,36,99.0,0,40.5,98,8.77,1.74,4.9,186,120,2.9,2 .8,0.0,-0.8,0.0,-3.9,4,
1720,36,99.0,0,40.5,98,8.77,1.74,4.9,186,120,2.8,2 .7,-0.8,5.5,0.0,-3.9,4,
1682,36,99.0,0,40.5,98,8.77,1.80,4.9,186,120,2.8,2 .9,-1.6,4.7,0.0,-3.9,4,
1688,36,99.0,0,40.5,98,8.77,1.78,4.9,186,120,2.9,2 .9,-1.6,5.5,0.0,-3.9,4,
1709,36,99.0,0,40.5,98,8.77,1.78,4.9,186,120,2.9,2 .9,3.9,5.5,0.0,-3.9,4,
1703,36,99.0,0,40.5,98,8.77,1.80,4.9,186,120,2.9,2 .9,3.9,6.3,0.0,-3.9,4,
1695,36,99.0,0,40.5,98,8.77,1.80,4.9,186,120,2.9,2 .9,4.7,7.0,0.0,-3.9,4,
1691,36,99.0,0,40.5,98,8.77,1.74,4.9,186,120,2.9,2 .9,5.5,8.6,0.0,-3.9,4,
1687,36,99.0,0,40.5,98,8.77,1.74,4.9,186,118,2.9,2 .9,5.5,9.4,0.0,-2.3,4,
1691,36,99.0,0,40.5,98,8.77,1.77,4.9,186,118,3.0,2 .9,6.3,3.1,0.0,-2.3,4,
1697,36,99.0,0,40.5,98,8.78,1.76,4.9,186,118,3.0,2 .9,7.8,3.1,0.0,-2.3,4,
1703,36,99.0,0,40.5,98,8.78,1.74,4.9,186,118,3.0,2 .9,9.4,2.4,0.8,-2.3,4,
1677,36,99.0,0,40.5,98,8.78,1.79,4.9,186,118,3.1,2 .8,10.2,1.6,0.8,-2.3,4,
1701,36,99.0,0,40.5,98,8.77,1.77,4.9,186,118,3.1,2 .8,3.1,1.6,0.8,-2.3,4,
1708,36,99.0,0,40.5,98,8.78,1.75,4.9,186,118,2.9,2 .8,3.9,0.8,0.8,-2.3,4,
1680,36,99.0,0,40.5,98,8.77,1.76,4.8,186,118,2.9,2 .8,3.1,0.0,0.8,-2.3,4,
1700,36,99.0,0,40.5,98,8.77,1.76,4.9,186,118,2.9,2 .8,3.1,0.0,0.8,-2.3,4,
1703,36,99.0,0,40.5,98,8.78,1.75,4.9,186,118,2.9,2 .9,2.4,0.0,0.8,-2.3,4,
1708,36,99.0,0,40.5,98,8.78,1.79,4.9,186,118,2.9,2 .7,1.6,3.9,0.8,-2.3,4,
1683,36,99.0,0,40.5,98,8.77,1.75,4.9,186,118,2.9,2 .9,0.0,3.9,0.8,-2.3,4,
1714,36,99.0,0,40.5,98,8.77,1.75,4.9,186,118,2.9,2 .9,-0.8,4.7,0.8,-2.3,4,
1703,36,99.0,0,40.5,98,8.78,1.78,4.8,186,118,2.9,2 .9,-1.6,4.7,0.8,-2.3,4,
1695,36,99.0,0,40.5,98,8.77,1.77,4.8,186,118,2.7,2 .8,-2.3,5.5,0.8,-2.3,4,
1678,36,99.0,0,40.5,98,8.77,1.81,4.9,186,116,2.8,2 .9,-2.3,6.3,0.8,-2.3,4,
1723,36,98.0,0,40.5,98,8.78,1.77,4.8,186,116,2.7,2 .9,3.1,7.8,0.8,-2.3,4,
1691,36,99.0,0,40.5,98,8.77,1.79,4.9,186,116,2.9,2 .9,3.1,1.6,0.8,-2.3,4,
1695,36,98.0,0,40.5,98,8.77,1.77,4.9,186,116,2.9,3 .0,3.9,8.6,0.8,-1.6,4,
1723,36,98.0,0,40.5,98,8.78,1.76,4.9,186,116,2.9,2 .9,4.7,8.6,0.8,-1.6,4,
1692,36,99.0,0,40.5,98,8.77,1.78,4.8,186,116,2.9,2 .8,4.7,3.9,0.8,-1.6,4,
1695,36,98.0,0,40.5,98,8.77,1.79,4.9,186,116,3.0,2 .9,5.5,3.9,0.8,-1.6,4,
1728,36,99.0,0,40.5,98,8.78,1.75,4.9,186,116,2.9,2 .8,7.0,3.1,0.8,-1.6,4,
1687,36,99.0,0,40.5,98,8.77,1.75,4.9,186,116,2.9,2 .8,8.6,2.4,0.8,-1.6,4,
1686,36,98.0,0,40.5,98,8.77,1.76,4.9,186,116,3.1,2 .9,9.4,1.6,0.8,-1.6,4,
1718,36,99.0,0,40.5,98,8.78,1.77,4.8,186,116,3.0,2 .7,10.9,1.6,1.6,-1.6,4,
1690,36,99.0,0,40.5,98,8.77,1.76,4.8,186,116,3.1,2 .7,10.9,0.8,1.6,-1.6,4,
1691,36,99.0,0,40.5,98,8.77,1.75,4.9,186,116,2.9,2 .7,3.9,0.0,1.6,-1.6,4,
1708,36,99.0,0,40.5,98,8.78,1.76,4.9,186,116,2.9,2 .7,3.9,5.5,1.6,-1.6,4,
1707,36,99.0,0,40.5,98,8.78,1.75,4.8,186,114,2.9,2 .9,3.1,5.5,1.6,-1.6,4,
1689,36,98.0,0,40.5,98,8.78,1.75,4.9,186,114,2.9,2 .9,2.4,6.3,1.6,-1.6,4,
1699,36,98.0,0,40.5,98,8.77,1.75,4.9,186,114,2.9,2 .9,1.6,7.0,1.6,-1.6,4,
1721,36,98.0,0,40.5,98,8.78,1.78,4.8,186,114,2.9,2 .9,1.6,7.0,1.6,-1.6,4,
1683,36,98.0,0,40.5,98,8.78,1.74,4.8,186,114,2.8,2 .9,0.0,7.8,1.6,-1.6,4,
1702,36,98.0,0,40.5,98,8.77,1.75,4.9,186,114,2.8,2 .9,0.0,3.1,1.6,-1.6,4,
1725,36,98.0,0,40.5,98,8.78,1.74,4.8,186,114,2.8,2 .8,0.0,3.1,1.6,-1.6,4,
1694,36,98.0,0,40.5,98,8.78,1.76,4.9,186,114,2.8,2 .8,4.7,2.4,1.6,-1.6,4,
1697,36,98.0,0,40.5,98,8.78,1.75,4.9,186,114,3.0,2 .9,4.7,2.4,1.6,-1.6,4,
1716,36,98.0,0,40.5,98,8.78,1.76,4.9,186,114,2.9,2 .7,5.5,1.6,1.6,-1.6,4,
1686,36,98.0,0,40.5,98,8.78,1.75,4.9,186,112,2.9,2 .7,6.3,0.8,1.6,-1.6,4,
1681,36,98.0,0,40.5,98,8.77,1.76,4.9,186,112,3.1,2 .9,7.0,0.0,1.6,-1.6,4,
1705,36,98.0,0,40.5,98,8.77,1.76,4.9,186,112,3.0,2 .7,7.8,5.5,1.6,-1.6,4,
1717,35,98.0,0,40.5,98,8.78,1.75,4.9,186,112,3.0,2 .9,8.6,5.5,1.6,-1.6,4,
1705,35,98.0,0,40.5,98,8.78,1.75,4.9,186,112,3.0,2 .9,2.4,6.3,2.4,-1.6,4,

[/pre]

[Chris@HPTuners]

seems we have some forum formatting issue, here so i just tidied it up a bit.

From the look of the data your LTFT's are moving around a bit. Checked your O2's?

[mrkrad]

yeah im wondering. I have o2 extensions and they are 70.5K miles old. I was not sure if the headers did that (pace-suckahs) or if one of the o2's are going bad.
They both seem to sweep to the same peak/trough though.

definitely odd.