Drive by wire Throttle body cleaning and maintenance

Here is the link to the cleaning process of throttle body and you can watch this procedure in video.

The drive by wire is the newer technology used in cars since 2007 or so. In Toyota it had been introduced in Toyota Yaris model year 2007. In the drive by wire technology the throttle body throttle plate is actuated by an electric motor instead of a mechanical wire and cable arrangement actuated by foot. In the drive by wire system the driver of a vehicle is footing on gas pedal which actuates a set of sensors. They can be some times magnetic sensors and sometimes variable resistors or potentiometers. So by footing on gas pedal a voltage signal is produced proportional to the pressure on the pedal. This voltage signal is feed then to the ECU or PCM of the vehicle. The ECU or PCM is using this signal as input. There are other inputs to the PCM also like MAF sensor, O2 or Oxygen sensor etc. Then ECU or PCM is deciding how much to open the throttle plate to ensure the correct psychometric ratio of fuel and air to get optimum engine performance. In such a case the TPS sensor is acting like a feed back signal sensor to ensure the exact mechanical position of the throttle plate.

The benefit of the drive by wire system is obvious as the ECU or PCM is controlling the throttle plate using an algorithm hence optimum performance and excellent fuel economy is the result. The drive by wire car present much more fuel economy and optimum performance than of the older days mechanical wire arrangement cars were. Also there is another benefit of easy cruise control feature is achieved without installing extra equipment as it was in the case of older mechanical actuated system.

The reason for the optimum performance and better fuel economy is the better control of ECU or PCM on the throttle plate in all driving conditions and situations. The conventional systems is using driver foot force to actuate the throttle plate in the throttle body. So a mechanical wire and cable arrangement is used. Hence the PCM is not controlling air instead it is only controlling fuel quantity to the fuel injectors in such designs. So the system is even a bit mechanical dependent. Whereas in the newer drive by wire system the pcm is controlling the throttle plate hence it controls the quantity of air along with quantity of fuel. By this way a sophisticated and much more efficient control is achieved which results in optimum performance and excellent fuel economy.

Drive by wire system is used in most new car makes and models. They are less pron to dust and dirt accumulation in the throttle body which cases the rough idle and low performance at slow speeds. Anyhow they are having problems when they accumulate dust and dirt. Here in the following lines I am explaining the way to clean and maintain the drive by wire throttle body for a Toyota Camry car.

Drive by wire throttle body cleaning

Locate the throttle body in your car. It is closed to air filter and air intake tube. You should have to remove the air intake tube, the filter box and some times battery also. Also remove the battery one terminal in case if you are not going to remove the battery from the vehicle.

Loose and remove all four bolts which are fastening the throttle body with the air intake. After removing all four bolts you may wiggle the throttle body left and right, up and down and discard it from the air intake and bring it off or the car.

Remove all the electrical connectors and plugs along with wiring harness to be able to remove the air intake pipe and throttle body. Keep the wiring harness side.

Remove the throttle body from the car and inspect it for dirt and carbon deposits accumulation. You will find it very dirty if the car passed more than four years of road like without cleaning the part.

Also see the condition of the air intake mesh. You will find it very dirty also. Clean it and replace the gasket if it is needed.

Bring the throttle body to the washing or cleaning bath and pore some solvent like regular gas or any other solvent of your choice for cleaning.

Clean the dirt and carbon deposits from the throttle body using a nylon brush. Also pore more and more solvent to wash the throttle body further.

Clean and wipe the throttle body using paper towel. By this way you will be able to remove the small dirt and carbon even more. In the result you will get a very cleaned throttle body.

Your throttle body should be cleaned and shine like a new unit. The throttle body should be cleaned to such a degree that the car you are working on should not come again for some four to five years back with same throttle body complaint. Keep in mind that the unsatisfied repair is a sin in the engineering world. Do proper and perfect repair to most reliable degree.

Calibration

The modern throttle bodies in the vehicles need calibration after cleaning them. For the calibration a bidirectional scan tool is required. The scan tool have a procedure to do the zero or factory calibration of throttle body after servicing it. By applying such procedure on can calibrate the throttle body and achieve the ideal idle speed of 600 to 700 rpm. If you don't have a bidirectional scan tool then the other way is to keep the vehicle running and cycle the key for several time. After a few days of use the ECU or PCM will learn the new state of throttle body and will set it to Zero calibration. But the best way is off course to calibrate it using a scan tool.

Here is a link to my other post on another type of throttle boy.
http://diycarmaint.blogspot.com/2017/01/throttle-body-cleaning-maintenance.html

Here is the link to my other throttle body cleaning video on my channel: