Can someone help me please.
A couple of months ago my 200hp ox66 started running a little funny at WOT is would act like it was running out of gas kind of surging or lagging a little. It has progressively gotten worse yesterday it was so bad i could hardly get up on plane. The thing cranks right up with a bump of the key and idles around fine. I have replaced all fuel lines, changed little fuel filter(the one in the clear canister), checked vent hose, replaced anti siphon valve at fuel tank with a nipple, replaced 3 low pressure pumps. I also cleaned oxygen sensor. Are these symptoms related at all to needing to decarb? I need help, all the shops around here are very busy and i don;t want to be without boat for a month!!!!

Thanks for any help