Hi. I have a model K3.91 M 1700 psi electric pressure washer. It recently started to pulse when the power was on but not spraying. Immediatley I thought "Leak". So I checked thoroughly and found a hairline crack in the cylinder head. I replaced that part and reassembled with no leaks. But still have the pulsing when power is on. When I press the trigger, it works normal except the pressure is quite a bit lower than it should be. Now I'm thinking it could be a pressure switch or something electrical. Does anyone have any sugestions of what it could be.? I'd really hate to put alot more money into this thing. Thanks