The Frakes novelisation of T2:Judgement Day gives an account of the T-1000's thought process after it was forcibly ejected from the back of the car. It seems that it assessed that it was wasteful of energy to continue active pursuit and that it would be more sensible to attempt to re-acquire/ambush his targets at another location. This is the same motivation that led it to Pescadero in the first place.
But now he was dropping way behind. Sarah had the pedal floored and
the liquid-metal killer had its limitations. It couldn’t catch them on
A moment later, the T-1000, slowing to a walk, watched the taillights
recede. The target’s escape meant nothing to it. The delay could only
be a measurement of time. Although terminators had internal
chronometers, the T-1000 did not. It was part of Skynet’s new design.
Knowledge of time had its uses, but in most cases of pursuit, it was
an unnecessary element. Time did not matter when the thing after you
could not be killed, could not be stopped, and would never tire.
The T-1000, blissfully unaware of anything except the target’s
projected escape route, glanced down. The liquid metal blob on the
asphalt began to shudder, then elongate, stretching like a liquid
finger until it touched Officer Austin’s “shoe,” flowing into it,
rejoining the main mass.
Time was only a temporary respite from inevitable.