good luck it only acts up under a load could be anything. so after all you have done you at a good starting point next get a hold of a scan tool and look at datastream what are the o2s doing first if there working fine just look at all else and make sure they are performing within specs that is were i would look next and i didn`t read you saying that you have replaced the fuel filter. how does that look? signed always stuck in diagnostics!
