Why is my Kärcher G 4000 OH not reaching high pressure?
- BBlake ShafferAug 21, 2025
If your Kärcher Pressure Washer isn't reaching high pressure, several factors could be the cause. The diameter of your garden hose might be too small; replace it with a 5/8 inch or larger hose. The water supply could be restricted; check the garden hose for kinks, leaks, or blockages. Ensure there's enough inlet water supply by turning the water on full force and checking the hose. The water inlet filter may be clogged; remove and rinse it in warm water. Also, check if the black detergent nozzle is attached; if so, remove it and attach a high-pressure nozzle. Finally, make sure the Remote Pressure Control regulator is at the highest setting.