How to fix it
Work through these in order, the most common causes come first.
Start With the Basics
Power source (electric): Check for a tripped GFCI outlet or breaker before assuming a unit problem, this alone resolves a large share of "won't start" cases.
Safety lock: Confirm the trigger gun's safety lock is disengaged, many units won't start or won't build pressure with it engaged.
Trigger during startup: Many models require the trigger to be squeezed while powering on to release residual pump pressure.
Diagnosing Your Specific Problem
Electric unit is completely dead, no sound at all: check the outlet, GFCI reset button, and try a different outlet or cord before assuming a motor failure.
Electric unit hums but the motor doesn't engage: may indicate a seized or stuck pump, especially after long storage, this typically needs professional service if it doesn't resolve with in the first minute of running.
Gas engine won't catch on pull-start: check fuel freshness first, then spark plug connection, then choke and fuel valve settings, roughly in that order of likelihood.
Gas engine turns over but doesn't fire: most likely a fouled spark plug or incorrect choke position for a cold start.
Unit worked fine last season, won't start this season: almost always stale fuel on gas units, or a tripped GFCI or dried pump seals on electric units that sat unused over winter.
Our picks
Products we recommend
As an Amazon Associate I earn from qualifying purchases. Picks are based on manufacturer specs, independent reviews and owner reports.
AR Blue Clean
1900 PSI sits right at the safe upper end for car exteriors without needing to dial anything down
- 1900 PSI, 1.51 GPM
- Bayonet-connect nozzles and accessories
- Onboard detergent tank
- Integrated hose reel
- Compact frame with onboard storage
✓ Pros
- 1900 PSI sits right at the safe upper end for car exteriors without needing to dial anything down
- Compact enough to store in a garage corner between washes, unlike bulkier driveway-focused units
- Budget price makes it an easy first pressure washer if car washing is the ma in use case
✕ Cons
- 1.51 GPM rinses a full-size vehicle a bit slower than higher-flow units
- Bayonet connectors are a less common fitting standard than quick-connect, worth checking foam cannon compatibility before buying one
- Lower build durability rating than the Karcher K5 over years of frequent use
Sun Joe
Standard quick-connect fitting works with the widest range of aftermarket foam cannons and car-wash attachments
- 2030 max PSI, 1.76 GPM max flow
- Dual detergent tanks
- 5 quick-connect nozzles including a 40-degree wide fan
- Standard quick-connect fitting, compatible with most foam cannons
- TSS auto shutoff
✓ Pros
- Standard quick-connect fitting works with the widest range of aftermarket foam cannons and car-wash attachments
- Dual detergent tanks let you keep a dedicated car soap loaded separately from an all-purpose cleaner
- Widest nozzle selection in this list for dialing in a safe, wide fan spread
✕ Cons
- 2030 PSI is more than a car needs, requires consistent nozzle and distance discipline
- Bulkier than the AR Blue Clean AR383 for a single-purpose car-washing setup
- No car-specific preset or reduced-pressure mode
Best overallGreenworks
Highest PSI-and-GPM combination of the electric models in this list, cuts driveway time noticeably versus sub-2000 PSI units
- 2300 max PSI, 2.3 GPM max flow
- TruBrushless motor with axial cam pump
- 25-foot kink-resistant hose
- 35-foot GFCI power cord
- 5 quick-connect nozzles including turbo
✓ Pros
- Highest PSI-and-GPM combination of the electric models in this list, cuts driveway time noticeably versus sub-2000 PSI units
- Brushless motor is quieter and rated for a longer service life than standard brushed motors
- 10-inch wheels make it easy to roll along a long driveway without dragging
✕ Cons
- Bulkier and heavier than compact electric models like the Greenworks GPW1501
- Still needs a household outlet with in cord range, a limitation gas units do not have
- No detergent auto-mix while spraying at full pressure, soap mode runs at reduced PSI
FAQ
Common questions
Why won't my electric pressure washer turn on at all?
Check the power source first: a tripped GFCI outlet or breaker is the single most common cause, since most electric pressure washers draw 13 to 15 amps and can trip a shared circuit, especially one running other appliances. After confirming power, check that the trigger gun's safety lock is disengaged, since most models won't start with the safety lock engaged.
Why does my gas pressure washer's engine not start?
Common causes include old or stale fuel (gas degrades after about 30 days without a stabilizer), a spark plug that's fouled or disconnected, the choke or fuel valve not set correctly for a cold start, or, on models with this feature, the trigger not being squeezed during pull-start to release built-up pressure that can prevent the pull cord from engaging fully.
Does the trigger gun need to be squeezed to start a pressure washer?
Both electric and gas pressure washers often require the trigger to be squeezed briefly during startup to release residual pressure in the pump and allow the motor or engine to engage. Check your specific model's manual, but this is a very common step that's easy to overlook.
Can a pressure washer that sat unused all winter fail to start?
Yes, this is extremely common. On gas units, stale fuel left in the tank or carburetor over winter is the most frequent cause. On electric units, it's less about the motor itself and more often a GFCI outlet that's tripped, or, less commonly, pump seals that have dried out and need a priming cycle before the unit builds pressure normally again.
Keep researching
Related guides & comparisons
