1992 Talon Tsi AWD Project

DSMlink LTFT Tuning

The Videos
E85 Global Calculation Info
DSMlink MAS/MAF Calibration Page
Calibrated BoostEst Curve
DSMlink LTFT Tuning
The DSM ECU Timing Curve
Magnus Crap
The Fuel Sump
Shep Stage 4 & Turbo
Dyno Session
2nd Dyno Session
Damaged Block
Damaged Block #2

Fuel Trim Calibration
1G's = LTFT Lo, Mid and Hi
2G's = LTFT Lo and Mid
The DSMlink owners manual contains a list of appropriate injector Global and Deadtime settings. Use these settings and input them in the fuel table. Once you input the correct Global value for your injector, do not touch it ever again. (Unless switching to E85) All other compensations to the injector flow will be made through the airflow and fuel sliders.


To keep things EXTREMELY simple, I've broken down the long term fuel trims to these sliders.
LTFT Lo = 50Hz Airflow Slider
LTFT Mid = 150Hz Airflow Slider
LTFT Hi = 250-400 Hz Airflow Slider
LTFT Lo = 50Hz Airflow Slider
LTFT Mid = 150-400Hz Airflow Slider
Adjusting fuel trims with the above information makes Rev MAFT calibration very easy. Obviously we still need MAFraw captured along with STFT and all the LTFT's. Also make sure you are at your thermostat's operating temperature.
Step 1) Rev to 50Hz
Step 2) LTFT lo + STFT = Your 50Hz adjustment
Example : If STFT is +7% and LTFT Lo is +3%, then adjust your 50Hz airflow slider 10% higher than it currently is now.
Step 3) Rev to 150Hz
Step 4) LTFT mid + STFT = Your 150Hz adjustment
Example : If STFT is -11% and LTFT Mid is +4%, then adjust your 150Hz airflow slider 7% lower than it currently is now. And continue to repeat for LTFT Hi for 1G's.
Step 5) Cruise on the road  until you can get a stable 250Hz
Step 6) Repeat equation until lower airflow sliders are calibrated
I also want to mention what the DSMlink manual suggests when LTFT Lo and LTFT mid are far apart from each other. If LTFT Lo is positive and LTFT mid is negative, then increase dead time. Vice Versa. This is another tool you can use when fine tuning LTFT's.
NOTE : You must be patient when calibrating the lower airflow sliders. The ECU will take it's time readjusting the LTFT's. The best thing to do is to calibrate the GMAF using the steps above and then just recheck them after a day of driving. Adjust again if neccesary.
Good Luck.