This means that the TPS voltage has fallen below the idle threshold that was previously set. To fix this, you'll need to run the throttle position sensor calibration.
To calibrate throttle position, the ignition should be on but the engine not running. For carbureted engines, make sure the choke is fully open and off the fast idle cam before beginning. Turn the knob to "SET" (Set Up System) and click to enter the setup menu. "TPS" (Calibrate TPS) will be shown and you can click the knob again to enter calibration mode. It will begin detecting the idle throttle position right away, so leave the pedal untouched.
When the display scrolls “PRESS ACCEL PEDAL”, push the accelerator pedal all the way to the floor and hold it. After a few seconds, “RELEASE ACCL. PEDAL” will scroll on the screen and you can release the pedal. “TPS SUCCESSFUL” will scroll if the setting completed. Afterward, it will show the measured closed and full throttle voltages. If an error occurs during calibration, the display will show the error and abort calibration. If this happens, you can try running the calibration again. If errors continue, you may need to check your wiring for problems.
If you are using a negative slope TPS, use our Shiftware tuning software to calibrate.
Possible TPS Calibration Errors as shown on the built-in display:
ACCEL PEDAL NOT PRESSD / ACCEL PEDAL NOT HELD
The throttle wasn’t pushed or held at maximum long enough for the test to complete. Accelerator pedal must be held for 3 seconds and voltage must not drop more than 0.168V below the maximum recorded value.
ACCEL PEDAL NOT RELEASED
The throttle wasn’t released within 5 seconds. The voltage must drop at least 0.96V below the maximum measured WOT value.
TPS NOT STABLE
The idle throttle position has changed values too drastically over the course of the calibration. The idle voltage is more than 0.6V greater than the lowest recorded value.
ERROR TPS LO = 0.00
The voltage is below the minimum allowed 0.2V during any of the tests.
