from what i understand through readings from proton website & learnings..

what actually happend when we suddenly ram the accel pad is,
1st, more air come in,
2nd, due to bernoulli principle, the air 'drives' the fuel to come out from inside a venturi tube alike..
3rd, they mix together and enter inlet manifold...

this whole process takes time..
sometimes, in sudden accel, more air come..
the air flow cannot drive fuel to go out the venturi instantly...
thus, creating a weak mixture to be burned in combustion chamber...
oh yeah, it lags just milisecond, maybe microseconds..
but, the impact to the engine performance is tremendous...

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