One of the component of an automatic transmission is the throttle valve (TV) or the kickdown cable which is attached to the linkage of the transmission. When the throttle is press down, the kickdown cable is pulled gradually along with the throttle’s position. This mainly provide force for downshifts of kickdown as well as upshifts when in higher speeds.
This works synchronously along with the gas pedal. Upon pressing the gas pedal all the way, the throttle valve’s position changes along with the gas pedal and this provides good timing in shifting and the car is running fine on the road. And then, the transmission will change gear when it reaches to a point where it is necessary towards the next gear until the engine speed picks up to another point where it will changes to the next gear.
When the time if the pedal gas isn’t press enough to have pressure or power to the engine, the throttle valve(TV) or kickdown cable won’t have much pressure to be able to change gear. Furthermore, this adjusts the transmission’s main line pressure as it helps the transmission shift into the required gear position whenever the car is accelerated.
Some automatic transmissions can burn up if this cable is broken or improperly adjusted so check that out regularly. Running a transmission with the kickdown cable is not on its proper adjustment, won’t only create early or delayed shifting or something like a symptom of a slipping transmission, but inaccurate line pressure at the same time. That means, whenever the throttle valve or kickdown cable is having a low pressure, this affects the main line pressure, making it low as well, burning the transmission clutch.
Throttle Valve (TV) or Kickdown Cable Adjustment
There comes a time when it is necessary to adjust the kickdown cable to its proper adjustment point. When you experience certain untimely shifting, whether it’s early or delayed shifting, although you have the right amount or level of transmission fluid and it’s in good condition, this is probably cause by the kickdown cable that is out of adjustment.
- Turn-off the car engine
- Find the throttle valve(TV) cable at the transmission linkage.
- Press down the D button or whatever lock it has in your car, then slide it until it will let go
- Open the throttle to open position and then release it
- When doing this, a click should be heard
- Be sure the cable returns without any binding when throttle is in released position
- This initial adjustment will most of the time set to high and need to be reduced to to proper pressure for smooth shifting
Should have any difficulty grasping what I’m outlining here, please watch the video below.
Video Showing Simple Kickdown Cable Adjustment
You can do a regular check on this or have your auto mechanic or auto repair and service center do this for you on a regular basis. Taking care of this small problem earlier can save you significant amount money doing major repairs as we discussed previously, repair costs can be expensive depending on model and the specific problem associated with it.
During the time you change the transmission fluid this should be check as well. If you let your auto service center do it routinely, ask them to check the throttle valve (TV) or kickdown cable as well, along with if it’s necessary to having a transmission flush.