I have a 2004 Dodge Ram 1500, 5.7L truck, These trucks have a drive-by-wire system where the gas pedal isn't physically connected to the throttle plate to control it.
Instead it uses a pedal position sensor to tell the PCM what position the pedal is at and adjusts the throttle plate accordingly.
For various reasons I'd like to add in a switch to bump the idle up just slightly, to around 1500 RPM or so. Or have a knob that can adjust the RPM infinitely.
So given the way the system works I'm thinking that if I tie a pot into the APPS (Accelerator Pedal Position Sensor) I would be able to adjust the resistance and control the idle speed with a knob or switched resistor.
The sensor itself is located under my battery, and a cable connects the pedal to the pedal position sensor.
Here is a description of it's operation from the service manual as well as a pinout. I still have to try and find some info about what those sensor wires do and which one of those would be sending the pedal signal to the throttle body. Which means I may try to find a salvage APPS to test and play around with.
The Accelerator Pedal Position Sensor (APPS) is a
linear potentiometer. It provides the Powertrain Control
Module (PCM) with a DC voltage signal proportional
to the angle, or position of the accelerator
pedal. The APPS signal is translated (along with
other sensors) to place the throttle plate (within the
throttle body) to a pre-determined position.
A mechanical cable is used between the accelerator
pedal and the APPS assembly. Although a cable is
used between the pedal and APPS, a mechanical
cable is not used at the throttle body. Throttle plate
position is electrically determined.
Instead it uses a pedal position sensor to tell the PCM what position the pedal is at and adjusts the throttle plate accordingly.
For various reasons I'd like to add in a switch to bump the idle up just slightly, to around 1500 RPM or so. Or have a knob that can adjust the RPM infinitely.
So given the way the system works I'm thinking that if I tie a pot into the APPS (Accelerator Pedal Position Sensor) I would be able to adjust the resistance and control the idle speed with a knob or switched resistor.
The sensor itself is located under my battery, and a cable connects the pedal to the pedal position sensor.
Here is a description of it's operation from the service manual as well as a pinout. I still have to try and find some info about what those sensor wires do and which one of those would be sending the pedal signal to the throttle body. Which means I may try to find a salvage APPS to test and play around with.
The Accelerator Pedal Position Sensor (APPS) is a
linear potentiometer. It provides the Powertrain Control
Module (PCM) with a DC voltage signal proportional
to the angle, or position of the accelerator
pedal. The APPS signal is translated (along with
other sensors) to place the throttle plate (within the
throttle body) to a pre-determined position.
A mechanical cable is used between the accelerator
pedal and the APPS assembly. Although a cable is
used between the pedal and APPS, a mechanical
cable is not used at the throttle body. Throttle plate
position is electrically determined.