I switch the pressure washer on motor starts pressure builds up motor stops. OK pull the trigger on the lance the moter starts sounds different water pressure low. Release trigger motor still runs.

When the power washer does not turn on, it is either due to no water flow or no electricity going to the power washer. In other words, either a water or electrical problem.
check water flow issue like this

1. The high pressure hose, spray gun and lance must be connected to the power washer.
2. The garden hose must be connected to the power washer using the garden hose adapter.
3. Turn the water completely on at the water faucet.
4. The power cord should not be plugged in.
5. Squeeze the trigger on the spray gun.
6. If there is water flow through the spray gun and lance shooting 10 - 25 feet, this confirms water flow is NOT the problem for the power washer not turning on.
7. If there is no water flow, perform the following troubleshooting procedures:
   a. Remove the lance, squeeze the trigger. If water flows, the lance is blocked. Use cleaning wire to clean the nozzle tip and try again.
   b. If no water flows with lance removed, turn the water off. Remove the spray gun from the high pressure hose. Turn the water on, if water flows, the gun is the problem. Reattach the gun, turn the water on and squeeze the trigger. Sometimes this unblocks the gun. If not, replace the spray gun.
   c. If no water flow with the gun removed, remove the high pressure hose, turn the water on to make sure there is no blockage in the hose. This is very unlikely but we need to make sure.
   d. If no water flows out of the water outlet, the quick connect garden hose adapter is problem. See Garden Hose Adapter troubleshooting.
8. For electrical solution check
9. The power switch was not turned on. Find the power switch and make sure the "-"side of the rocker switch is pushed down. "O" = Off and "¾" = On.
10. Next, make sure the power cord is plugged directly into an outlet and NOT into an extension cord. The directions do say not to use an extension cord.
11. Each time the power cord is plugged in to an outlet, the Reset button on the GFCI module must be pressed down to connect to electricity.
12. Check to see if the Reset button has been pressed.
13. Next, confirm the small plastic window below the Reset button shows RED in the window. The RED color is not a light but a RED screen that slides into the window when the Reset button is pressed down. Because it is not a light, it can be hard to see in low light. If you are unsure, press the TEST button down. If the GFCI was set and RED was in the window, you will hear and feel a "click."
14. The RED color must stay in the window once the button is released. This confirms there is electricity going to the power washer.
15. If the RED color goes away when the Reset button is released, there is NO electricity going to the unit. Try another outlet until the RED stays in the window.
16. Now if the unit turns ON for a second or two with the Reset button pressed and the power switched on, it is working as it should. All that is left to do at this point is to squeeze the trigger on the spray gun and the power washer will turn on. When the trigger is released, the power washer will turn off. This is due to the Total Stop System (TSS) that only turns the unit on when water is flowing through the power washer. When the trigger is released, water flow stops which the TSS sensed and immediately shuts the unit off. a) So to review, if the Reset button has been pressed and is holding and the power switch is ON, the power washer is supposed to start up for a second or two and immediately shut off. At this point all you need to do is squeeze the trigger; the unit will turn on.

Hi Cliff:
My experience is that the pump pressures prevent the engine from starting, so we hold the trigger while starting.
My brother has cut a wedge of wood that he uses to jam the trigger open to bypass the problem. It can get a bit wild if the wand is not secured when the unit is started..

POSSIBLE this look picture hose coupling with water stop put on the tap side or lime in valves after long time or a nozzle with dirt close beaten
clogged nozzle on the lance

Bypass not working (lyme)
if you disconnect the lance and the handle grip is giving enough water and water comes out then the nozzle clean it with a little paperclip.

As it's a new machine, check your operators manual it has a trouble shooting guide. But it sounds like the fuel maybe the problem, do not use old fuel as it deteriorates over time.

sounds like your unit has a bypass problem either needs adjustment or replaced

Try keeping the trigger on the lance pulled while you try and start this lets the pressure out and should be easier to start.

Pressure washer when you first try to start them that stop underload. We had the same type of problem with 11 hp Honda if you hold the trigger open the motor will be under less load we found by running the motor for about a minute it would work normally. Remember to make sure the water hose is turned on pull the trigger on, until water is coming out of the wand , now try and start the motor but also hold the trigger open, now you will not be building maximum pressure, after about a minute release the trigger and see if it keeps running.

Sounds to me like you have a partially blocked jet on the end os the lance. If this is not clear then the machine will not start correctly.

turn off water and machine electrics.

remove high pressure hose from front of machine, this may be tight if there is still pressure in the system.
turn on water, when water comes out of machine hose outlet turn on machine. does the machine turn on and water flow increase, if so you probably have a blocked lance jet or trigger.

remove lance extension if fitted and fit hose back to machine, try again. If its ok then this proves you have a blocked lance jet, maybea poke about with some stiff wire will free the obstruction.

If this doesnt bring on the machine you probably have a jammed pressure switch on the pump.

this pressure switch turns on the pump when the trigger is pulled and switches the motor off when the trigger is released.

hope this helps.

unloader valve sticking in the pump head. remove unloader valve/ pressure reducing valve as per parts manual.

It will probably be caked up in white crystal type deposits if its an aluminium pump head. clean off the deposits and inspect the 'o' rings. if 'o' rings ok , apply silicon grease and refit.

It could also be a partially blocked lance jet not allowing enough water to come out of the lance if it is a flow sensitive unloader valve.