Another stalling coming to idle issue

[askkmb]

Hello, im having an issue with a car when coming to stop it dies but only happens a every once in a while. A lot of times it comes down to idle just fine and no underspeed whatsoever. I have played with throttle follower, throttle cracker, rolling idle and a bunch more. I made underspeed table aggresive to see if it would keep timing up when the rpm got low, seemed to help a bit but not much. I also did open the throttle set screw a little higher to make sure it gets enough airflow. Looking at the scanner it seems that sometimes when the throttle follower has a slow rate down it comes down stable but sometimes the follower drop at fast rate and thats when it stalls. Might not have to do with that but looking at any possible cause right now. Ill attach a picture where it shows coming down to idle after accelerating various times with no problem but eventually it dies where the follower drops down fast. Thanks for your help.follower logging.PNG

[ryan_axberg]

It would be nice if you post up a tune and a log. You don't need your throttle follower decay to last so long. It is probably down to your braf, and your throttle cracker table. It would help if you would log iac position also.

[68camaroLS6]

Well had the same issue with my 68 camaro with LS6 especially when the AC was running. If you have access to hptuners, check your spark advance in park and gear from 0 to 800 rpm. If the timing is low in this area, the engine will stall. At least this is what I was experiencing.

So, I raised the timing to 25 degrees from 0 to 400 rpm range and 22 degree at 800 rpm. They call this as a stall saver. Now the issue is resolved. My desired idle rpm is at 850 rpm

[askkmb]

I don't think it's a timing issue because when it wants to die, the timing jumps up to try and save it. I have tried adding to the cracker table which seemed to help but not where I like it. I did try the Russ K idle config today to close in on the raf table but it needs work. I will post a log tomorrow, but i adjusted idle set screw until my IAC count was 60, then reset TPS.

Anything else I can try? What is the best procedure to adjust the cracker table?

[68camaroLS6]

I also suggest checking out idle tune videos made by ChopperDoc181 on youtube. He has got some detailed videos on idle tuning but his method is different than Russk?s method.

[askkmb]

5. stall after rev.hpl


Heres a recent log. It idles very nice and most of the times it wont die but i still have that issue. The log shows where i rev it in gear(but not driving) and it once almost stall and saves it, and after a second it still dies. I will check those vids out

[askkmb]

Well still cant figure this out. First used Russ Ks idle config and now used info from chopperdoc on youtube and i still have the same issue. I upped idle speed to 925 to try and see what it would do and after finishing raf tuning and everything i started adjusting IAC according to chopperdocs guide and it just doesnt work. What else should i try. One thing i see is that when it wants to stall i the IAC opens a little but once it goes to about 3-400 rpm it just closes and gives up. The spark goes up to try and save it too but isnt enough. My IAC counts were within 40-60 but after tuning the IAC the counts have dropped a little.