Advance Mutiplier resetting on restart?

[mad_sb]

Originally Posted by feldy

I did notice the other day the IAM Value stuck until I cranked the car. I started to log before I cranked the car and the value was there and then reset to .7 when the car got spark. ill try to find it when im not drinking and playing gta

yes, i have seen that as well. I though ohh awesome, it was just my imagination, then i cranked it.... lol

[mad_sb]

Originally Posted by ft_sjo

Is this really a problem that needs fixing?

I'm not sure. The reason i am interested is because not all cars do this. Also, based on everything i have ever read on subaru knock control, it should not work this way. IAM is there for long term knock correction.

when IAM resets after every drive cycle, you have no long term knock correction. Setting the initial value to a safe number results in a delay in getting full performance every time you drive the car. Setting it to 1 could result in excessive knock everytime you drive the car if you get bad or slightly worse gas than normal or weather changes etc.

[feldy]

Originally Posted by mad_sb

I'm not sure. The reason i am interested is because not all cars do this. Also, based on everything i have ever read on subaru knock control, it should not work this way. IAM is there for long term knock correction.

when IAM resets after every drive cycle, you have no long term knock correction. Setting the initial value to a safe number results in a delay in getting full performance every time you drive the car. Setting it to 1 could result in excessive knock everytime you drive the car if you get bad or slightly worse gas than normal or weather changes etc.

Ill see if I can trick it this morning and see what happens.

[ft_sjo]

Originally Posted by mad_sb

I'm not sure. The reason i am interested is because not all cars do this. Also, based on everything i have ever read on subaru knock control, it should not work this way. IAM is there for long term knock correction.

when IAM resets after every drive cycle, you have no long term knock correction. Setting the initial value to a safe number results in a delay in getting full performance every time you drive the car. Setting it to 1 could result in excessive knock everytime you drive the car if you get bad or slightly worse gas than normal or weather changes etc.

Would you really want long term global correction in a country where fuel quality and options vary so greatly? I think i'd prefer it to figure it out on a per-tank basis, especially if it were forced induction, although me being paranoid i'd rather just map it safe without any adaptive advance into the unknown.

[mad_sb]

Originally Posted by ft_sjo

Would you really want long term global correction in a country where fuel quality and options vary so greatly?..

Yes, that's exactly why i want it to work. I'm about to drive across the country and don't want to be staring at my laptop for 2,200 miles worrying about it unlearning the knock correction it just learned eveytime i stop for a pee lol.

[feldy]

I just confirmed no matter the time difference of the car being shut off it resets. I just went from IAM value of 1 shut the car down restart not even 30 seconds later and boom back to .7

[regal]

This has been known from day one, the car is 0.7 IAM stock The 1.0 "boost" in timing after driving hard on 100 octane (exaggerating) was just so they could squeeze that magic 200hp number out of this knock limited engine. Tuners here have been tuning for a 0.7 IAM, if you get a bad tank of gas there is still room to drop below that. This is the first I've heard that the push start models don't start at 0.7 every time, has that been verified?

[xjohnx]

Originally Posted by feldy

I just confirmed no matter the time difference of the car being shut off it resets. I just went from IAM value of 1 shut the car down restart not even 30 seconds later and boom back to .7

weird.i'd be interested to see if this behavior persists for you with the 01C rom version

[ft_sjo]

x01x defaults to 0.7. Push button cars are no different, well mine isn't. Not on x0xG.

[xjohnx]

Originally Posted by ft_sjo

x01x defaults to 0.7. Push button cars are no different, well mine isn't. Not on x0xG.

ZA1JA01C (ecutek modified) does not reset the IAM on my car unless I perform a DTC reset.

[mad_sb]

Originally Posted by regal

This has been known from day one, the car is 0.7 IAM stock The 1.0 "boost" in timing after driving hard on 100 octane (exaggerating) was just so they could squeeze that magic 200hp number out of this knock limited engine. Tuners here have been tuning for a 0.7 IAM, if you get a bad tank of gas there is still room to drop below that. This is the first I've heard that the push start models don't start at 0.7 every time, has that been verified?

This is wrong, and not how subaru's long term knock control (IAM system) has worked in the past. IAM is supposed to persist unless the ecu is reset. As others have shown, on some 86's IAM is persistent, on others it is not. Hence this thread. We are just trying to figure out why it persists on some cars and not on others.

[mad_sb]

Originally Posted by ft_sjo

x01x defaults to 0.7. Push button cars are no different, well mine isn't. Not on x0xG.

I'll add you to the "My IAM resests every startup" camp and also, the BRZedit camp.

I need a couple of cars with un-touched ecu's so i can check them and see if they are resetting.

[regal]

Originally Posted by mad_sb

This is wrong, and not how subaru's long term knock control (IAM system) has worked in the past. IAM is supposed to persist unless the ecu is reset. As others have shown, on some 86's IAM is persistent, on others it is not. Hence this thread. We are just trying to figure out why it persists on some cars and not on others.

I didn't say it was how it works with Subaru's of the past but it was one of the first thing our group checked a year ago. This car is Subaru's first DI, the highest C.R. street Subaru boxer sold, the stock tune is uh different.

I hope I am wrong wrong but every car around here resets to 0.7 IAM after ignition off. We just assumed the 1.0 IAM was so Subaru could claim 200hp.

[brn12345]

How are you guys checking which Rom your using? And is there a way to check it without a flashed ecu?