How does an engine's intake manifold leak affect my car's braking performance?
The brake pedal is attached to a vacuum brake booster, which utilises vacuum power to make the brake pedal more responsive when it is stepped on.
The vacuum is created when air is drawn by the engine's intake manifold. A leak in the manifold adversely affects this function. This in turn results in less braking assistance from the brake booster.
A leak also causes more air to be drawn into the engine cylinder. This leads to less efficient engine combustion.
AUTOMOBILE ASSOCIATION OF SINGAPORE