Can someone tell me how my logs look?

stage 1 tune, just looking for some feedback from the community regarding it..

 

what could be improved, what looks wrong/right, etc..

romraiderlog_20100726_074509.csv

Looks good to me. Fuel trims are decent, the one knock event that was learned is already correcting itself out. No knock in the log and boost control looks okay. Is this a MickeyD map?

nah, this isnt a MickeyD's map...

 

thanks for the reply .. any other input is appreciated

AFR is off too much at WOT. Should be 0.2 not 2.0.

AFR is off too much at WOT. Should be 0.2 not 2.0.

 

Hummm D range fuel trims are a little high but not as bad as others I have seen. Also he has no real knock to speak of per LV.

Just wondering what is up with D-range. Mine is NEVER that far off.

I don't think the positive 2% correction in the 40+ g/s range is too big of a deal. If it was negative 2% and the fueling targets were already really lean then it could be a problem but in this case it is adding a very small amount of fuel in the 40+ range.

 

It's really difficult imo to get scaling dead on. Aside from climate changes, driving style will also change the fuel trims. For example, when I'm scaling in closed loop and I drive like a grandma all my fuel trims are within 1% or so. When I drive harder in closed loop on the same maf scaling all my trims go up a percent or 2. This can mostly be accounted for with the manifold relative pressure compensation table, but a lot of people don't tune that.

Less is better, but 2% ain't much IMO.

 

It can take a looong time for the D trim to actually become useful. Unless you have some long steep hills that will let you run 40-60 g/s for extended periods without accelerating, you're only going to be in that range for very short periods.

I thought anything within 5% was acceptable, per MerchGod. Stock cars sometimes come with that variance.

All kinds of things including climate, most breathing mods and driving style can effect the fuel trim numbers.

 

As far as what is acceptable it depends on how rich/lean your tune is. If you're setup for an AFR of 11.1 and you're 5% negative, then you're hitting closer to 11.7 which is not really within the range of safety.

Looks good to me

Looks good!

I thought that if the D range is -5%, that means the car WAS running rich, ie the ecu is now pulling fuel in that range to get the afr it wants? Do I have that backwards?

That is what I know too. Negative means pulling gas, positive means adding, as in running lean, no?

Looks good!

I thought that if the D range is -5%, that means the car WAS running rich, ie the ecu is now pulling fuel in that range to get the afr it wants? Do I have that backwards?

 

If you drive in the 40 maf/g range for a long time (highway) and that 40ish range is off -%5 then yes, the computer is pulling 5% fuel to try to maintain 14.7:1 mixture.

 

The problem comes in when you get into the wot maf range. Whatever % is in the 40+ range applies to the rest of the maf scale. So you could have the open loop region dialed in really well but it would still be pulling 5% because the 40maf range was off.

 

So if your open loop maf range is dialed in, and targeting an already lean mixture, and then the -5% gets applied it can cause further leaning which can be dangerous.

I hadn't considered how the a/f learning impacted open loop. I'm thinking 99% of the data in the 'D' range is WOT, so if it's pulling 5% fuel, I would think after a flash you would be running a little rich, slowly leaning out to target. I would be more concerned if I was adding fuel - meaning running leaner than target every time the learning is reset.

I hadn't considered how the a/f learning impacted open loop. I'm thinking 99% of the data in the 'D' range is WOT, so if it's pulling 5% fuel, I would think after a flash you would be running a little rich, slowly leaning out to target. I would be more concerned if I was adding fuel - meaning running leaner than target every time the learning is reset.

 

If you have a tune and your closed to open loop delay is 0'd then most of the data in the D range is going to be from 40-50 and maybe into the 60s as the ecu doesn't make corrections to the open loop fuel targets other than the D range fuel trim. You can log the cl/ol delay as well as maf g/s and see when it changes. When I'm scaling my maf, I set the delay to half the stock value so I can get some usable a/f correction data up to about the 80 maf range.

 

If you're adding fuel, (+5%) then your WOT range would be richer than your open loop targets and typically safer though you may lose some power.

Looks good to me

thanks again;)

Noob question alert.

AFR affected by environment, such as temps? I recall seeing 11.2 at WOT but now when I get into boost and/or WOT, I get 11.0 solid. What # does it cut off reading, isn't it right at 11?

I noticed my afr reads slightly different on different logs. As long as it is not changing during wot I assume it's ok. I don't know why it reads differently, but your theory sounds like it could very well be right.

Noob question alert.

AFR affected by environment, such as temps? I recall seeing 11.2 at WOT but now when I get into boost and/or WOT, I get 11.0 solid. What # does it cut off reading, isn't it right at 11?

If its not a wideband generally it doesn't matter under WOT.

The stock sensor is reasonably accurate at WOT (any conditions, really) if you move it to the downpipe. But it will only read down to about 11.1 or 11.2.

FYI, I looked through some old logs, and my afr either pegs at 11.02 or 11.14 at wot.

If its not a wideband generally it doesn't matter under WOT.

Do you mean under 11 it doesn't matter, or not that much at all given the inaccuracy?

Do you mean under 11 it doesn't matter, or not that much at all given the inaccuracy?

If in OEM placement under high exhaust pressure it is inaccurate. The only time it should be considered in these conditions is if it starts to display values indicating your mix is leaning out.