Help...!!! my K4.99m started to pulse last year but I put up with it (I think its called lethagy) I then left it outside like an idiot (worst winter for years) ....Tried to use it and water poured out from underneath..did a bit of investigation and found that the see through plastic input pipe had cracked....I then found this site and bought a new pipe and an accessories holder clip (did I mention I broke this when it fell over..!) anyway fitted the above and I had a pressue washer again..! but it was still pulsing....I'd tried the air-lock solution but no joy so went down the new cylinder head route...arrived today and I fitted it...aghhhh...the machine is still pulsing..(by the way I can't see any crack hairline or otherwise in the cylinder head...) Any suggestion as to what I can try next would be appreciated...its had a new lance and wands....