02 ls1 idle issue

Ive done quite a bit of searching and found others with a similar issue but none with a direct answer. Im new to tuning and was looking for some direction. Car is a 02 ls1 fbo m6 with a 228r cam. runs and idles great other than one small issue. when i stab the throttle or clutch in the idle drops to around 500 then comes back up to the requested 800. doesnt really hunt just drops one time and comes back up. from what ive read it has to do with base airflow, the throttle blade is opened up to .71 on the tps and IAC counts are around 40 warm, i was told this is about the limit on opening the blade. I added some base idle airflow also and havent really gained on the issue. is this a idle timing issue or do i need more base airflow? thanks.

https://forum.hptuners.com/showthrea...Idle-dips-dies


Post 11 try this

Also you might wanna bring down that TPS

thanks, i will try that. only question is it does this both clutch in and clutch out?

iac counts should be 40-60 so you are good there. you can open the throttle as far as you need to drop the iac counts down to this range(which it looks like you have done)
the part that gets overlooked or misunderstood is the calibration of the tps sensor after the mechanical adjustment has been made. the tps sensor should be adjusted to read an off throttle voltage of .48-.5v with a common wot voltage of around max 4.61v.
for larger cams requiring the plate to be adjusted beyond the adjustment range, you can remove the stopping nub on the back and open the notches a tad to allow further adjustment.
after each blade and tps adjustment you must perform a tps reset.
simple google search should get your the tps reset steps.

fueling plays a huge role in cylinder loading at idle so in order to get the proper BRAF and idle values you must constantly keep the idle fuel error below +-5% error. this should reduce most of the issues.

Ive reset the tps each time and successfully got it to read 0% at closed throttle. so you're saying i should adjust the tps to get the voltages back to a stock reading?

double check your idle voltage cal by monitoring a status bit for engine state or by monitoring idle trims.
if the trims move and/or the status bit designated idle loop active then you should be fine. there is a threshold voltage (which i dont remember) if exceeded at closed throttle will prevent the ecu from activating idle control circuits.

if your activating the idle control circuits then you likely have a braf and fueling error.
do you have a tune and logs so the rest of us can see what your working with and the results you are receiving?

i dont have any logs at the moment but heres my tune. i have played with the base idle airflow from what it shows here with no real results.

just for reference the car has done this ever since the cam install, both on stock tuning and after the tune. the issue has improved with opening the throttle blade but has never completely gone away making me think its something else that needs adjusting in the tune. ive been seeing alot of talk about base timing with the underspeed/overspeed but not sure where to start with those parameters.

i typically reduce my over under speed tables from stock so they dont correct as hard.
are you tuning maf or ve? maf isnt active until 4000 rpm
my ignition advance at idle is somewhere around 19-21* typically. i play with it until i find a balance between maximum idle vacuum and how smooth it runs.
i match my idle advance table to my main ignition tables in the lower load so the transition between tables remains smooth.

ok. i appreciate the info. i havent changed any of the fueling yet, still need to get my wideband in. ill look at the timing and get some logs this weekend. im really new to this and am nervous about changing things unless i know exactly what im doing lol. definitely appreciate the advice, thanks.