If these trims were generated with at least an hour of stop and go driving, then I suggest increasing the scaling by 10%, i.e., set the injector scaling value to the value closest to 870. Then increase all the latency values by 0.040. Let us know what trims you get after at least an hour of stop and go driving with the revised settings.

 

Ok, so I got a chance to log them at different setting today. Here is what I got:

Scaling:860

4.6875 3.360
7.03125 1.728
9.375 1.512
11.7188 1.008
14.0625 0.816
16.4062 0.528
18.6768 0.408

LTFT LOW: 0.2
LTFT MID: -5.5

 

Almost there. Increase scaling to value closest to but not less than 903, and increase all latency values by 0.020.

 

Ok, so I got a chance to log them again at different setting. Here is what I got:

Scaling: 914

4.6875 3.384
7.03125 1.752
9.375 1.560
11.7188 1.032
14.0625 0.840
16.4062 0.552
18.6768 0.456

LTFT LOW: 5.98
LTFT MID: 2.6

 

See next post.

 

Increase all latencies by 0.050.

 

just a question, can you damage the injectors if you over ms them per voltage or will you just add too much fuel and blow the spark out? take this example, if the injectors are the same what would be the findings from running either voltage?
V ms (1) ms (2)
4.6875 3.312 4.752
7.03125 1.68 2.352
9.375 1.032 1.848
11.7188 0.672 1.32
14.0625 0.432 0.912
16.4062 0.264 0.696
18.6768 0.144 0.408

thanks
Andy

 

Won't damage the injectors... car will just run like crap with bad latency and/or scaling values.

 

I have my rear O2 disabled and removed. Therefore there is no way for me to read fuel trims. Does the ECU still figure out what to do with a rich/lean condition even though the trims are not visible to me?


Is there a clever way to read fuel trims without going back in and turning the sensor back on?

As of now I have no way to read fuel trims unless I turn the sensor back on. However my wideband says my idle and cruise is 14.2 instead of 14.7. In this situation do you change injector scaling or latencies? I suspect the ECU has pulled all it can from the AFR.

 

deleted

I stand corrected

 

Ok, so I got a chance to log them again at different setting it was to much when added .050 trim was 0 for low and -8 for mid. Here is what I got when added 0.020

Scaling: 914

4.6875 3.408
7.03125 1.776
9.375 1.584
11.7188 1.056
14.0625 0.864
16.4062 0.576
18.6768 0.480

LTFT LOW: 0
LTFT MID: -4.9

 

That's a bit strange because the latency value should have a much stronger affect on the LTFT low. Now that you're getting close, I think you need a few more drive cycles to get a better feel for the trims before further changes are made. Report back the fuel trims after driving for a few days with the current settings.

 

I thought if the rear o2 was disabled your trims would be as well. Has something to do with the ECU and not the O2 itself.

 

eh... try again

 

If the rear o2 is disabled via periphery, the fuel trims will not register...