Answer first
On a Willz dishwasher, leaving dishes dirty usually comes down to detergent type, dose and water hardness, with loading pattern next. Change one thing at a time and run the same soil again, because that is the only way to tell chemistry from mechanics here.
What you actually observe
- Food left on the load after a full cycle — Usually in the same places on the rack, cycle after cycle.
- A gritty film on glasses and the inside of the tub — Redeposited soil rather than soil that was never removed.
- NEAR MISS — there is standing water in the bottom after the cycle — That is a drainage fault, and soil in that water is why the load is dirty; start with the drainage page.
Causes, most likely first on this platform
- Detergent type, dose and water hardness — First on a cost-reduced machine and first by a wide margin: with no water-hardness compensation and a short main wash, the detergent has to do all of the work, and the wrong type or dose shows up immediately.
- Loading pattern — Second. A smaller wash pump has less pressure to spare, so shadowing and nesting cost this machine more coverage than they would cost a better-equipped one.
- Water that is not hot enough at the start of the cycle — Third: there is no meaningful onboard heating on many machines in this class, so the temperature that arrives is the temperature you get.
- A choked filter and coarse screen — Fourth, and the one most owners have never looked at: soil that cannot leave the sump is sprayed back over the load for the rest of the cycle.
Check in this order, and why that order
- Change one thing about the detergent and run the same load again — Type, dose and a rinse aid are free to test and they explain more poor results than every part on this list put together. It goes first: top-ranked above, and free to rule out.
- Look at where the poor results are on the rack — A pattern that repeats in the same place is loading or coverage, not chemistry. Second: the next cause in the ranking, and this check separates it from the first.
- Run the kitchen tap hot before starting the cycle — If results improve, the machine was filling with cold water for its first and most important fill. Third, once both checks above come back clean.
What an owner can safely check
- Run the same soil on a fresh detergent tab, correctly dosed, with rinse aid topped up — Use the detergent dispenser rather than throwing a tab in the base, or it dissolves during the pre-wash and is gone by the main one.
About 60 min
- Reload with nothing nesting and nothing tall blocking the upper arm, then repeat the cycle — Spin each arm by hand before closing the door to be sure nothing fouls it.
About 15 min
- Run the nearest hot tap until the water is hot, then start the cycle immediately — Free, and it removes a long cold pipe from the equation.
About 5 min
- STOP HERE if the next step needs the machine unplugged and a panel removed — Anything behind the outer panel of a machine holding water and mains wiring is a service call.
Before you take anything off
Safety
Unplug the machine or switch off its breaker before removing any panel; a capacitor can hold a charge after the power is off, and this machine holds water and mains wiring in one cabinet. Never defeat the door latch switch, and never reach into a sump or a drain pump that is still plugged in: broken glass goes through a rubber glove.
Where an owner check ends
Call once the filter is clean, the arms spin freely, the detergent is right and the results have not changed, because what is left is pressure, heat or a diverter and all three are behind the tub. There is no hazard in waiting, only dishes. On a cost-reduced platform the cheap repairs are worth doing and the expensive ones rarely are, so get the cause named before agreeing to anything.
Where to go next in this class
What this page does not cover
This page is written for the Willz dishwasher as a class, not for one family or model line. Where a family- or model-specific page exists for your unit it is linked here, and it is the more specific answer. Not here: part numbers, wiring colours, torque figures, panel sequences and component ratings, which differ by family.
Links: - [Willz dishwasher leaking onto the floor: where it starts](/blog/willz-dishwasher-water-leak) - [Willz dishwasher not draining: water left in the bottom](/blog/willz-dishwasher-drainage-failure) - [Wizard dishwasher leaving dishes dirty: what to check first](/blog/wizard-dishwasher-cleaning-performance)
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
