help with idle with dbw

[josey]

Hi guys,

i need some help,

there was my topic which was related to this problem but i was sure that i had problem with PID settings which i see now i dont.

 

Thing is, i have 2.0L with 272deg cams, 75mm DBW throttle body,

idle control is set to open loop dbw, ignition timing is used from main ignition table which is 16deg.

and engine idle smooth and perfect at 900 or 1000rpm,

until i touch throttle and release it quickly.

than problem starts, idle starrt bouncing from 500-1500rpm and then i have to catch it on throttle, and slowly release it, and than engine idle smooth again.

same problem is when engine fan turns on.

Thing is that when im tryng to move on parking engine stall every time i press clutch, same thing on traffic lights, i have to stop and engine stall.

i tried to set idle control to closed loop, but it was even worse, because butterfly on throttle body is to big and 0.2% movement made changes about 300-500rmp

 

So i search forum and i found good help here:

 

Idle ignition control turned on, and engine idle much much better, it catches idle target RPM in second,  and car is finally drivable, BUT, problem with dropping rpm stays.

If i release throttle quickly rpm drops to almost stall, below 500rpm

 

can you guide me what can i try to fix this ?

maybe add more idle base timing?

here is idle ign correction table

 

 

thanks guys

 

 

 

 

 

 

 

[josey]

timing from 14deg rised to 20deg

same thing happening.

here is vid how that looks like.

ideas?

https://vid.me/Wpy6

 

 

 

Edited March 31, 2017 by josey

[Adamw]

It will be easier to help if you can post up a pc log with all parameters recorded and a copy of your map.

 

[josey]

can you send me email? 

thanks

[josey]

kind of an update,

vacuum leaks check, no leaks

spark plugs changed,

oil changed,

throttle body checked, it was clean, and no stucks from 0-100%

same thing happens.

 

revs drop like a rock and engine stalls

 

only thing i could do is raise idle to 1200rpm because it was impossible to drive in traffic, and now with idle at 1200rpm situation is better, maybe 1 of 20 times engine stalls, that is lets say acceptable.

 

honestly i dont know what else to try. do you have any suggestions?

 

 

 

 

 

 

[josey]

update

added more resolution around idle, i didnt have time to fine tune it but things are much much better.

I think i can get max smooth idle this way.

 

idle is back on 1000 rpm and on stop, drops only 100rpm.

 

 

Edited April 13, 2017 by josey