Another idle question

[driver456]

I have SD tune and have not had a idle problem in awhile.I started running 100 octane gas when I go race,Thats when I think it started to idle funny,I think.The idle starts to swing and bounce from 500rpm to 1500rpm.I get it to idle fine in park,But in gear it bounce's,Then I get it to idle fine in gear and then it bounce's in park.So I figured let me put the MAF back on.Long story short,I got it to idle pretty good,But not solid in gear,In park its rock solid.When I set {B0120} back to 4000rpm it bounce's again.So I have it set at 500rpm and it idle's fairly good.Thank God for Road Runner:grin:.Anybody have any idea's................Paul

[Ritch]

Did you ever solve this? I just ran a tank of last years fuel with octane boost added (did not run engine from last October) and my idle is moving around a bit too. Last year I was working with IAT/timing to steady up the original cam change issues. I thought I had it figured.