Erratic pressure could be caused by which of the following?

Erratic pressure in a hydraulic system can indeed be caused by a defective accumulator. An accumulator is a crucial component that stores hydraulic fluid under pressure. It serves as a buffer for the system, absorbing pressure spikes and maintaining a steady flow. When an accumulator is defective, it can lead to fluctuations in pressure due to the inability to maintain proper fluid volume at desired pressure levels. This defect may manifest as erratic behavior in the hydraulic pressure, as the system struggles to compensate for the malfunctioning component.

Other factors, while they can contribute to pressure issues, may not directly cause erratic pressure in the same way. For example, a loss of fluid volume typically leads to a decrease in overall pressure rather than erratic fluctuations. A broken return line might create a pressure drop or leakage, but it would not necessarily result in erratic pressure. Similarly, a blocked filter might cause higher pressure due to resistance but would not result in erratic behavior. Thus, a defective accumulator is the most relevant factor linked to erratic pressure in a hydraulic system.