so i was going through my bin (8747) this evening trying to find something that would stand out as being a little funky since my idle is surging slightly and attempting to stall. was looking in my SA table and was just wondering if 24* of timing is enough...especially with the cold bias nearly 10 take out timing? the bias is a removal of timing correct? so a total 14* at idle (cold) is that enough? it still does it when its warmed up also. never stalls in park, just surges, but it will attempt multiple times in gear to stall, and sometimes succeed. my target idle is set to 700, and IAC steps target at 14.

any ideas what to mess with? or not mess with?

 

I idle at 17 on warm coolant. cold coolant I recall is 12. Not sure if that is optimal BUT was better than 24 I had before. 224/240 .05 114 LSA

 

i don't know if your auto or man. but do you know if the target IAC steps should be aimed for in gear or in park?

 

I am manual. I have EBL so I have two RPM tables one for drive and one park/neutral. My original EBL.bin was an auto so I suspect I would see an obvious difference one being higher RPM's(park). Those are commanded RPMs so the ECU is moving IAC to attain. Now IAC stems vs. throttle blade is a balancing act. Last I looked I am idleing 700 with 5steps. As you move the throttle SS the IAC responds. 5-10 is about right.

As far as which one to use I suspect both. I nust have changed mine 10X. Currently with manual I like 700 rpms. I lock SA at idle(1) and injector msec on is stable at 2.00. IAC does move up down around 5 steps to try to hold. I do use a VAFPR so not sure if that helps idle or hinders.

 

hey Ronny, do you use the SA cold bias constant? mine's set at 10* so my timing at idle and colder is only 14* would i be in big trouble if i zeroed out that bias?

 

I never touched it. I do however idle on cold engine(air temps 60F) at 10 deg SA and warm I idle 17 d SA.

 

Abit more timing wouldnt hurt. You can try abit more and see if that helps your idle. Usually does help.

 

ill give it a shot thanks