Adv multiplier of. 89 e85 oft
 

Hey guys, I filled up another tank of e85 and swapped my header out and my adv multiplier dropped to. 89. Suggestions?

Also to add this is happening at idle and moving.

we can t help without seeing a log
adv multiplier goes down if a lot of knocking is happening, and surely it doesnt knock while at idle with ethanol rich fuel
it can knock however as soon as you start moving if something is really off, but if you don t provide a log and info about the tune you loaded into your car, nobody is gonna help

Wait to see if it goes back up to 1.....

Could be lots things log would help


Could be mew header or overpipe hitting on chassis fooling knock sensor or low ethanol content e85 are your LTFT high negitive values like over -5% would indicate low ethanol content e85

Ltft is above 2 most of the time. I'm changing my oil today so I'll check if it's hitting.

Nope.....

is it e85 or like e51 flex?

My post was really just something to say the IAM is not the be-all and end-all. The IAM will not go back up unless you hit certain parameters. It is not necessarily an indiator that things are bad. The IAM will not increase at idle or low RPM/low load so you could cause the IAM to drop and then do whole drive cycles that you do not meet the criteria for it to increase again. I really wouldn't be that bothered with an IAM of 0.9, you're not losing that much performance (probably 1 degree max) and it won't take much for it to reduce that much, which itself depends on where you are in the ignition advance table at the time of the cause - you would lose more from a big knock correction event. As @steve99 said, it could just be physical contact.

To put it in perspective, Cosworth have said that anything up to -3 or -4 of correction is not an issue. That's probably an IAM of 0.6 on an OFT map.....

It's about e67

i haven t heard about that before. so that interesting for me

where I live, 100ron fuel is pretty inconsistent so i usually accept casual -1 or -1,4 specially on tip-in lowish rpm events
but i also use a magnitude of -0.7 for minimum correction on single event, instead of -1.05 of. stock

do you think the ecu would be smart enough to pull the same amount of timing with a minimum magnitude of - 0.7 like it would do with the stock - 1.05, or a -4 (-0.7x6)with "my" tune is actually stronger than a -4 with stock logic (-1.05x4)?

if yes,
do you think Cosworth saying -4 not doing damage, was referring of a magnitude of -1.05?

im guessing you dont have a flex kit, so im going to guess thats your issue

Not too sure if that's the issue tbh, my Ltft is above 5 now

ok if your iam is not returning to 1, and its not going any lower. It might just mean you havent driven in the load/rpm range where knock occurred so the ecu hasnt seen if the knock is consistent.

try doing two or 3 light throttle runs through the rpm range from 2000 to 7000 in say second, just light steady throttle not hard acceletation, this should reset iam to 1


[ame]https://www.youtube.com/watch?v=k7oa-EFUIfE[/ame]