SD LTFT+STFT cruise what I do wrong?

[Torque_Vector]

My car has already been tuned and I was put in speed density. I am running no MAF just an IAT. I don't know why in the tune they put the MAF fail to 1 it must not have to be 0? And nothing is checked for p0101,0102,0103.

Anyway I attached my files. All I did was leave everything the same just went into the scanner and logged LTFT+STFT and then copied the table and pasted Multiply by % - half in the VE table and wrote the calibration. Then I went for a drive and logged them again and then compared the two to see if the cells got closer to 0 and they actually look like they got worse and went more -? I am not sure what I am doing wrong? BTW this is my first attempt at this.

I am trying to log the LTFT+STFT and adjust to make them closer to 0 in the 2000 RPM range where they look more negative.

Thanks for any input.

323is original dyno tune - LTFT+STFT adj1.hpt
323is original dyno tune.hpt
after LTFT+STFT adj1.hpl
before - in town driving.hpl

[mcfarlnd]

Long term fuel trim is stored memory. Did you reset the fuel trims before starting to log? Personally i would utilize a Wideband but, if you have to use fuel trims, i would turn off long term trims and use short term only.

[mowton]

mcfarlnd is correct about resetting the fuel trims before each logging session but using the LTFT+STFT will actually compensate for that as the STFT will be developed against the erroneous LTFT thus cancelling its potential error. I would recommend adding the Fuel Trim Cell as a filter to preclude idle and decel data from contaminating your error data. It is [6310]<16 for version 3.0 or [PID.6310]<16 for version 2,24. I also add ECT>176 and use the commanded Lambda/AFR Channel (PID) to filter out excursions into PE during closed loop street tuning.

So in version 3.0, the filter looks like this...[5.242]>176 AND [6310]<16 AND [what ever commanded you have in your Channel/Table]> X. X can equal .95 for lambda or 13 for AFR

Ed M

[Torque_Vector]

Long term fuel trim is stored memory. Did you reset the fuel trims before starting to log? Personally i would utilize a Wideband but, if you have to use fuel trims, i would turn off long term trims and use short term only.

No, I did not, I will from now on. Thanks.

mcfarlnd is correct about resetting the fuel trims before each logging session but using the LTFT+STFT will actually compensate for that as the STFT will be developed against the erroneous LTFT thus cancelling its potential error. I would recommend adding the Fuel Trim Cell as a filter to preclude idle and decel data from contaminating your error data. It is [6310]<16 for version 3.0 or [PID.6310]<16 for version 2,24. I also add ECT>176 and use the commanded Lambda/AFR Channel (PID) to filter out excursions into PE during closed loop street tuning.

So in version 3.0, the filter looks like this...[5.242]>176 AND [6310]<16 AND [what ever commanded you have in your Channel/Table]> X. X can equal .95 for lambda or 13 for AFR

Ed M

I did have the filter setup shown in my picture below, but the commanded AFR is a good idea. Thanks.

[6310]<15 & [50090.155]>0

Will this format work or is the syntax/logic not correct? Also I had 15 not 16 for FTC so I will change that.

LTFT + STFT filter.PNG

[mowton]

I did have the filter setup shown in my picture below, but the commanded AFR is a good idea. Thanks.

[6310]<15 & [50090.155]>0

Will this format work or is the syntax/logic not correct? Also I had 15 not 16 for FTC so I will change that.

Yes I believe, i was having trouble because I was using lower case (and) but Keith fixed that a few versions ago. I've not used the & for AND but should work. Test it with the Chart and Zoom to isolate to the applicable expression and then in the Graph use the View Zoom Data Range Only to see if filter is actually working.

Ed M

[2002ZO6HDSandCAM]

What does this do?

[cobaltssoverbooster]

What does this do?

they are filtering the data field.
For all combustion engines, the engines will operate in 5 general load ranges which you may know or have heard of: idle/cruise/deceleration/medium acceleration/ and everyone's favorite wide open throttle.
problems generally occur in idle or cruise because the engines (especially modified ones), can start to overlap data fields between idle/cruise/and decel.
the filters these guys are applying to the data field are filtering out a specific section, such as cruise, that way when the data is corrected it is only corrected based off the limits in which the engine is operating at cruise.
same thing can apply for idle adjusting...by removing the data that is above the ranges of the engines idle operations, you tune specifically for idle alone.

[2002ZO6HDSandCAM]

Sorry I don't want to take away from anyone else getting help, but can someone take a look at mine. please before I blow it up.

[Asylumwarp]

The log doesn't look horrible, you just got some fine tuning to do.