How fuel mixture is supplied while clutch alone is released and not accelerator pedal is not pressed

[issaq]

On a flat ground, when the engine is engaged with first gear ,accelerator pedal not pressed and clutch is slowly released ,at a point vehicle starts moving .

Without pressing acc..pedal , how fuel-mixture is feeded to the engine ?. Because at this condition the throttle valve will be in fully closed condition , right?

 

[berkshire]

You would be running on the idle bleed circuit.
Depending on the type of fuel injection some engins have an rpm sensor to compensate for additional loads such as an airconditioner kicking in.
B.E.

 

[hydroman247]

If the RPM of the engine drops, the ECU will detect this and pump in more fuel although it will have a limit and it is still easy to stall most non Diesel powered vehicles.

 

[dgallup]

Many newer vehicles have eliminated the separate idle air control valve and gone to an electronic throttle valve (drive by wire). These can open the throttle as much as needed to keep the engine from stalling. On mt 2003 350Z I can climb hills with my foot off the throttle when I'm stuck in traffic and just idling along. I can also feel it kick in if I leave the car in gear and coast up to a traffic light. In the 6th gear the throttle will open at about 20 mph.

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

 

[SomptingGuy]

Driving a diesel using just the clutch pedal is a fun (if nerdy) pass-time. On an empty road it's a good challenge to go through all the gears. My car runs at about 30+ mph in top gear at idle.

- Steve

 

[mattsooty]

In a modern gasoline engine, in the condition you describe.
With 0% Pedal you are in idle speed control, whereby instead of a desired torque by the driver a desired engine speed is maintained, by a varying torque.
The torque is split into two parts - slow (air) & fast (spark) whilst lambda=1 is maintained.
Ideal conditions are for the air amount to be just enough so that the spark is held midway between max advance & retard with the desired speed being maintained.
The set point speed is maintained with a pid controller, using the fast path for small corrections & the slow path for bigger corrections.

Ms