A pedal adjustment system for an automobile has an accelerator cable and a master cylinder pushrod with a free end, the system having a brake pedal secured to a lower end of a brake pedal arm and an accelerator pedal secured to a lower end of an accelerator pedal arm. The adjustment of the brake pedal arm is effected through pivoting about the free end of the master cylinder pushrod, which pivotally engages the brake pedal arm between its ends, the pivoting being done by imposing a reversible force from an electric motor and gearbox assembly attached to an upper end of the brake pedal arm. The accelerator pedal arm, an upper end of which engages the accelerator cable, is adjusted in unison with the brake pedal arm through providing an accelerator pedal adjustment link, an upper end of which is coaxial with the brake pedal arm and a lower end of which is pivotally attached to the accelerator pedal arm at a location between the upper and lower ends of the accelerator pedal arm.
Most vehicles equipped with Power Adjustable Pedals will help you to adjust the pedals as you’re driving (and the 2014 Chevy Silverado is no exception) in the event you forgot to adjust them before you put the car in gear or maybe didn’t quite fine tune them enough.
Symptoms of a Bad or Failing Throttle/Accelerator Pedal Position Sensor
The days of constantly adjusting the throttle cable because of a loose nut on the carburetor are long gone. Today’s modern cars, trucks, and SUVs have an electronic throttle control system that contains an accelerator pedal position (APP) sensor. This sensor’s primary function is to monitor the position of the throttle pedal and send an electronic signal to open the throttle body as you depress the gas pedal. Although this device often lasts the entire lifespan of your vehicle, there are occasions when it will fail, wear out or needs to be replaced.
The APP sensor mainly tells your engine how fast or slow to drive when you press the gas pedal. When you’re pressing down or lifting off the throttle, it sends an electrical signal to the vehicle’s ECU or ECM as it’s also referred to, and then transmits that signal to the fuel system. The main reason why this part would fail is due to exposure to high heat as it’s typically located on the floorboard and next to the firewall of the vehicle. Unfortunately, this part can’t be repaired, so when a certified mechanic diagnoses that there is a problem with this device, you’ll be needing to replace the accelerator pedal position sensor.
Like most parts on the vehicle, a bad or failing APP sensor will display a few warning symptoms including triggering error codes, warning lights and a few physical symptoms that should make the driver notice that a problem exists. Few of these warning signs are listed below.
1. Engine throttle is inconsistent
When you press on the gas pedal, your engine should respond directly and instantly. However, when a problem with the APP sensor exists, the vehicle’s ability to consistently accelerate or even decelerate as directed by the driver will be reduced. This can lead to a serious safety situation as essentially the driver is not in control of the vehicle.
2. Engine does not run efficiently
When the APP sensor is not functioning in proper manner, it will also have problems with fuel efficiency. Besides monitoring and applying throttle pressure to the throttle body, it also stabilizes the throttle control. It’s designed to take input from the driver, but steady the application of fuel pressure as it relays the information from the ECU towards the throttle body of the vehicle. If the sensor is not able to transmit this information to the ECU correctly because of a loose wire, being worn out or have broken entirely, you’ll notice a huge difference in fuel economy.
3. Check that Engine Light comes on
Since the APP sensor is monitored by the ECU, it is one of those parts that will trigger an error code in the ECU when an issue is discovered. This will signal the Check Engine Light to illuminate itself on the dashboard. Anytime this light is on, you should take it seriously as there are a lot of components that will trigger this warning light.
Installing Power Adjustable Pedals
Basically, it is a direct swap, 13mm sockets just for everything. Its recommend to have a deep well, and a ton of extension bars to get around it.
Removal of pedals
- First, take off the lower dash trim (28mm bolts, then yank off).
- Take pin off brake pedal going towards master cylinder (You’ll see a rod with a yellow pin). Note how the brake switch is wired in on the car to be installed.
- Take off the cable linkage going to the accelerator: Protip – Put a wrench in the throttle to hold it half way open in order to get more cable leverage inside, There’s a little clip helps to hold it in.
- Unbolting the assembly. Power pedals is one solid assembly and old fashion is two, one brake and one accelerator.
- There are two bolts directly above of the pedals, and 4 nuts holding at the brake pedal and 2 at the accelerator.
- To make my life easier, it is recommended to unbolt the steering column to the rack, and took the
- U-joint is pushed out, and set aside for more space to work.
- For removing current brake pedal switch: You need to get to the tabs on the back side, without taking the dash apart, just get a long screwdriver and do it from underneath with the lower dash cover off.
Slide out the pedals and undo the brake switch (there are two, one should be part of the rod going to the brake cylinder, one above, a nice bright green switch, that twists out.
- Slide the assembly into the spot where the old pedals used to be, and bolt in. Attach the brake pedal to the brake cylinder while installing the switch as it was removed. Install the green switch by inserting and twisting in and then, zip tie the wiring so it will not be in the way. Attach the throttle linkage
Now, the Wiring part-
This part is quite simple for Gen4.5’s, and written for 4.5’s with the switch on the instrument cluster panel.
While harvesting, cut as much harness as possible from your donor car.
There are total of 7 wires-
Three Blacks – Ground – Find a ground anywhere.
One Blue/White – Interior Light circuit, tap in behind your light switch.
One Red wire – 12V+ In, I tapped into my ignition switch for power.
One Pink Black
There are two wires present on your pedal assembly: Pink/Black, and Blue/Red. Attach these two with the switch.
Once all that is done, the installation process is complete.