AAZ lumpy running+smokey

[flying haggis]

Hi all just done a heart transplant on my bus (jx-aaz) problem is it won't run properly it's very lumpy then cuts out and it's mega smokey (grey with a tinge of black),I've just noticed some fuel on the timing belt would a pump seal cause this or would it be best to fit the jx pump as its still the aaz pump
Also would the valve timing cause this,I don't think it's this as its more misfiring before it dies but I'm stumped also the throttle lever has been removed to be modded would this cause anything to go Pete tong?????
I'm thinking it's pump or an injector issue but just to see what you guys think