Systems and methods for controlling piston pumps

A controller configured to be operatively coupled to a reductant insertion assembly comprising a first pump configured to insert a reductant into a selective catalytic reduction system, the controller programmed to perform operations comprising:

• receive a first insertion command comprising information for activating the first pump for a first duty cycle, and for providing a first insertion interval between subsequent activations of the first pump;
• set an insertion interval timer for the first insertion interval, start the insertion interval timer, record an elapsed time period from the start of the insertion interval timer, and activate the first pump for the first duty cycle at the time of starting the insertion interval timer;
• receive a second insertion command comprising information for activating the first pump for a second duty cycle, and for providing a second insertion interval between subsequent activations of the first pump, the second insertion interval being different than the first insertion interval;
• and
• in response to determining that that the second insertion interval is smaller than the elapsed time period recorded by the insertion interval timer, set the insertion interval timer for the second insertion interval, start the insertion interval timer, and if the first pump is not already activated, activate the first pump for the second duty cycle at the time of starting the insertion interval timer.