ECMlink Target AFR maxoct table

[AWD-Tony]

I want to tweek my target afr's for better gas mileage so I came up with the map below. We don't really use the upper right & lower left corners, and anything past your rev limit. I noticed that crusing at 80mph my afr's were in the 10-12's. Unfortunately, I wasn't logging this. Do you see any issues with this table? This is for 93

You must be logged in to view this image or video.

 

[steve]

If you were cruising, how were you getting 10-12 AFRs? You should have been in closed loop cruising.

 

[1990TSIAWDTALON]

My cruise AFR's were always about stoich. 14.5-15.5
Are you on speed density Tony?

 

[AWD-Tony]

Yes I'm on SD. This is my current table and I guess I'm about here cruising at 80mph

You must be logged in to view this image or video.

 

[1990TSIAWDTALON]

Change your settings in your SD table at those points to lean it out. It's what I do anyway. I don't even mess with the AFREst (but I may be doing things wrong). It has always changed my AFR's that way. Especially during cruise.

 

[AWD-Tony]

Change your settings in your SD table at those points to lean it out. It's what I do anyway. I don't even mess with the AFREst (but I may be doing things wrong). It has always changed my AFR's that way. Especially during cruise.

I can do that but I want to lean out some other transition areas also. Then use the tool in link to make the adjustments. Just to make sure it's not too lean in the area's I made changes to.

 

[habitatguy187]

You should probably also change your open loop thresholds as well if you're cruising in the 4k range

 

[AWD-Tony]

You should probably also change your open loop thresholds as well if you're cruising in the 4k range

That's a good idea. How about these changes?

You must be logged in to view this image or video.

 

[habitatguy187]

Well, I'm really not sure. I don't know how to calculate the load values. You can start with those and then take it on a cruise and log when and at what cell it switches into open loop and adjust as needed.

 

[habitatguy187]

Ok so the load factor is the column on the left of the map. I would move them to about .7 for the immediate and maybe .65 for the delayed. Your throttle % needs to go way up. It needs to be equal to or slightly more than the throttle position when cruising at 4k and 4.5k

You must be logged in to view this image or video.

 

[AWD-Tony]

I'll have to tinker with it and see what works. I'll post results when I'm done. Thanks all!!

 

[AWD-Tony]

So the car is in closed loop and rpms are about 3500, so I'm going to make adjustments to those cells. I originally thought it was richer but looking at the log, it's off by too much.

You must be logged in to view this image or video.

I'll be loading this

You must be logged in to view this image or video.

 

[steve]

So the car is in closed loop and rpms are about 3500, so I'm going to make adjustments to those cells. I originally thought it was richer but looking at the log, it's off by too much.

If the car is in closed loop you won't be adjusting anything with that table regardless of the RPM. That table only applies in open loop.

 

[habitatguy187]

Right. The only way to manipulate closed-loop afrs is by simulating narrowband and changing your narrowband switchover point.

If the car is running rich in closed loop, I would adjust the SD table.

 

[AWD-Tony]

If the car is in closed loop you won't be adjusting anything with that table regardless of the RPM. That table only applies in open loop.

I needed a refresher on closed loop operations .

Right. The only way to manipulate closed-loop afrs is by simulating narrowband and changing your narrowband switchover point.

If the car is running rich in closed loop, I would adjust the SD table.

Yup. I’m not using narrowband sim so just going to adjust the SD table.

Thanks fellas!!

 

[habitatguy187]

It's so crazy how quickly I forget tuning stuff. If I don't touch it for awhile it all goes out the window

 

[AWD-Tony]

It's so crazy how quickly I forget tuning stuff. If I don't touch it for awhile it all goes out the window

Seriously. It has been a few years since I visited that page.

 

[ist dwa]

What your are trying Tony won't work. These are o2 feed back cars. The ecu will just keep compensating..... unless you took out a lot of global to the point the fuel trims are maxed out then it could start to run lean, then wot would get real scary. I suppose you could try removing a lot of fuel in the SD table at cruise points but I feel the car would just start to run real shitty.

I tried a million years ago in a safc to do something similar where I took my 3500 point and leaned it all the way out and went for a hwy drive to Detroit...... no change in mpg.

 

[AWD-Tony]

I lowered the cells and it’s good now. Leaving my global Aaron, she’s the t word for boobies . Are you going to Middletown anytime soon?

 

[jed344]

I have tried this years ago just to see what happens. I almost suspect the ecu always targets 14.7 unless in open loop as i never got any results other then ECU trying to hit 14.7.

 

[steve]

I have tried this years ago just to see what happens. I almost suspect the ecu always targets 14.7 unless in open loop as i never got any results other then ECU trying to hit 14.7.

No suspecting needed, that's what Closed Loop does. It uses the feedback from the narrowband sensor to maintain a 14.7:1 average.

It's only in Open Loop that the ECU uses the maps to target something else.

 

[danl]

What your are trying Tony won't work. These are o2 feed back cars. The ecu will just keep compensating..... unless you took out a lot of global to the point the fuel trims are maxed out then it could start to run lean, then wot would get real scary. I suppose you could try removing a lot of fuel in the SD table at cruise points but I feel the car would just start to run real shitty.

I tried a million years ago in a safc to do something similar where I took my 3500 point and leaned it all the way out and went for a hwy drive to Detroit...... no change in mpg.

I did a similar thing in my evo 9 except I was using a wideband and told the ecu to target 17:1 during cruise. It lacked power and misfired during transitions. Best mpg was using stoichiometric, 14.7:1. Thus, You can increase mpg by extending your closed loop operating range for higher rpm and a bit more load.

OP:
If you really want to increase mpg, drive slower. Air resistance is the largest force acting against you at highway speeds and it grows with the square of velocity. Ie 50mph is four times the air resistance as 25mph. Reduce speed by 5-10 mph and you will see significant gains in mpg.

 

[AWD-Tony]

So I lowered VE values being used at that speed and now it in the 14's. Not constant but much better now as before it would stay at 13's constantly. I'm still in the process of fine tuning the VE

You must be logged in to view this image or video.

 

[import solutions]

Just match trims with dead time and use sd adjust option and it should line.
Closed loop always will target 14.7 redardless what open loop maps are , and at ecmlink isnt an option to change that

 

[habitatguy187]

Closed loop always will target 14.7 redardless what open loop maps are , and at ecmlink isnt an option to change that

You can change it, IF you're using a wideband to run narrowband simulation. You change the narrowband switchover voltage point which effectively changes the closed loop target afr