How about this code for ISR? would it run faster?
ISR(TIMER1_COMPA_vect) { //Interrupt at freq of 250Hz
distance = getDistance(Lsensor);
pressure = getPressure(Psensor);
prSwitch = getPswitch(Pswitch);
temp = getTemperature(tmp);
Fldtemp = getTemperature(Fluidtmp);
toprint = 0; //reset buffer
toprint += drive;
toprint += ' ';
toprint += distance;
toprint += ' ';
toprint += pressure;
toprint += ' ';
toprint += prSwitch;
toprint += ' ';
toprint += temp;
toprint += ' ';
toprint += Fldtemp;
Serial.println(toprint);
}