The most common Murrieta dishwasher complaint. The leading cause is scale build-up in the spray arms. Hard water minerals accumulate inside the small holes on the spray arm surfaces and progressively block the water jets that clean the dishes. Over 2 to 3 years without descaling, spray arm output drops significantly and cleaning quality degrades even though the dishwasher appears to be functioning normally.
Diagnosis is visual: remove the spray arms and hold them up to a light. If most of the small holes are visibly restricted or blocked, scale is the problem. Cleaning takes 30 minutes with a citric acid soak and costs $95 with the diagnostic waived. Replacing the spray arm assembly (the "diagnosis" a generalist technician often gives) costs $180 to $350 and does not solve the underlying water quality issue.
Secondary causes of poor cleaning: a failing wash pump motor (rare), a clogged filter at the bottom of the tub (a homeowner check), or a control board issue preventing proper cycle execution.










