1. Non-Responsive Throttle
The first sign of throttle control failure is a non-responsive throttle. This happens when you press the throttle but you do not get a quick response in terms of faster acceleration. You will feel a weak throttle response and at times a jitter before your car accelerates.
One way that can happen is when the ETC is not getting proper electronic signals from the gas pedal. The ETC works great only when it receives proper signals. It is possible that a relay has gone bad or a wire has been cut loose from the ETC. No matter what the issue, you are bound to lose throttle response.
In the worst case, you might not get throttle response at all leading your car to stall in the middle of the road. As soon as this happens, you are advised to visit your nearest certified mechanic who has the expertise to deal with such a situation. If you are a DIY mechanic you can even take a look around the throttle body to identify any issues with the throttle wiring or the throttle positioning sensor.
2. Hesitating Throttle
If the ETC is damaged due to any reason, the throttle control light will enlighten in your dash. A damaged ETC will send improper signals to the throttle positioning sensor and your throttle will act erratically. This hesitation is minor in the beginning but it keeps on increasing till a time comes when the throttle is not responding to the acceleration pedal at all.
Furthermore, a hesitant throttle is a safety risk for you and for others on the road. You might get into an accident and damage property or life. In order to be safe, you should visit the mechanic at the first signs of failure.
3. Limited Acceleration
If things get serious with the ETC you might not only see a throttle control light
coming on in your dash but you would also feel you cannot accelerate your car more than a certain point. This situation is deliberate and is done by the ECU to protect the engine from damage. This is called the limp mode, which is a safe mode to keep the innards of the engine safe.