The new Jetta electronic throttle starts instantly at high idle speed.

There may be several situations that can lead to high idle speed:

1, improper cleaning of the throttle leads to the failure of the stepping motor. When cleaning, the carbon deposit should be wiped off with a soft cloth stained with cleaning agent, instead of spraying the nozzle directly into the accelerator, so that the cleaning liquid will flow into the stepping motor and cause damage. You can wash it again and try again. 2. Check the water temperature sensor. If there is something wrong with the signal from the water temperature sensor, ECU will judge that the engine is running at low temperature and mislead more fuel injection to increase the speed. This is the reason why the idle speed of the cold machine is high. When the water temperature reaches and the signal from the sensor passes, the engine will slow down.

3. Check the solenoid valve of the carbon canister, which is a black carbon canister on the left side of the engine compartment. The function of carbon canister is to collect gasoline vapor to prevent air pollution, and put the collected gasoline vapor into the steam inlet pipe to burn in the engine. Air intake is controlled by solenoid valve. When idling, the solenoid valve is closed, and when the speed exceeds 1200 rpm, the gasoline vapor is opened to enter the intake passage. If the solenoid valve fails and is in a normally open state, the actual air intake of ECU is greater than the standard air intake at idle speed.

4, nozzle wear, fuel injection is greater than the standard.

5. Battery problem. If the battery voltage is lower than 14V when the engine is running, the ECU will misjudge it as charging the battery at an increased idle speed. It is recommended to check the voltage. 6. For some old cars (more than 654.38+ 10,000 kilometers), we should also pay attention to checking the vacuum tube of the engine. If the vacuum tube leaks or is blocked, it will also lead to an increase in idle speed, and its symptom is a slow speed increase.