Method for sensing and clearing throttle plate obstruction
View Patent ↗An electronic throttle control system and method for detecting a throttle plate obstruction when the ignition key is on and the engine is either not running or running, and for clearing the throttle plate obstruction before a fault setting is set by the ECU.
1. A method for clearing an obstruction from around the throttle plate of a throttle body operable to provide air to a vehicle engine, said method comprising the steps of:
a) providing an electronic throttle control receiving an operating signal from an electronic control unit operable to control the movement of said throttle plate;
b) detecting an ignition-on condition;
c) detecting a stuck throttle plate condition;
d) upon detecting the conditions of steps b) and c), causing said throttle plate obstruction to be cleared by said electronic throttle control by a high frequency output signal variation received by the electronic throttle control from the electronic control unit; and
detecting that the engine is not running;
wherein said stuck throttle detecting step utilizes a proportional-integral-derivative feedback loop control logic programmed in said electronic control unit.
2. A method in accordance with claim 1 wherein said control logic for detecting said stuck throttle plate condition uses at least one of a throttle position error, a throttle position derivative and an integral of throttle position error.
3. A method for clearing an obstruction from around the throttle plate of a throttle body operable to provide air to a vehicle engine, said method comprising the steps of:
a) providing an electronic throttle control receiving an operating signal from an electronic control unit operable to control the movement of said throttle plate;
b) detecting an ignition-on condition;
c) detecting a stuck throttle plate condition;
d) upon detecting the conditions of steps b) and c), causing said throttle plate obstruction to be cleared by said electronic throttle control by a high frequency output signal variation received by the electronic throttle control from the electronic control unit;
detecting that the engine is running,
determining that a minimal throttle plate angular movement has occurred for a prescribed period of time, and
determining a throttle position error
wherein said stuck throttle condition detecting step is performed by determining whether said throttle position error has exceeded a predetermined threshold value.
4. A method for clearing an obstruction from around the throttle plate of a throttle body operable to provide air to a vehicle engine, said method comprising the steps of:
a) providing an electronic throttle control receiving an operating signal from an electronic control unit operable to control the movement of said throttle plate;
b) detecting an ignition-on condition;
c) detecting a stuck throttle plate condition; and
d) upon detecting the conditions of steps b) and c), causing said throttle plate obstruction to be cleared by said electronic throttle control by a high frequency output signal variation received by the electronic throttle control from the electronic control unit;
wherein step d) is initiated only if a predetermined number of obstruction clearing steps as prescribed by step d) have not been exceeded.
5. A method for clearing an obstruction from around the throttle plate of a throttle body operable to provide air to a vehicle engine, said method comprising the steps of:
a) providing an electronic throttle control receiving an operating signal from an electronic control unit operable to control the movement of said throttle plate;
b) detecting an ignition-on condition;
c) detecting a stuck throttle plate condition;
d) upon detecting the conditions of steps b) and c), causing said throttle plate obstruction to be cleared by said electronic throttle control by a high frequency output signal variation received by the electronic throttle control from the electronic control unit;
establishing a first length of time for operating said obstruction clearing step d) and discontinuing the high frequency output signal when a time for operating said obstruction clearing step equals said established length of time;
disabling step d) from occurring after discontinuing the high frequency output signal;
establishing a second length of time measured after discontinuing said high frequency output signal; and
re-enabling step d) after said second length of time has passed.