Catapillar fault code 151 has to do with engine coolant temperature high, possibly low coolant level OR a clogged DPF, depending on where your google search leads you. Fault code 102 fmi 4 relates to the intake manifold pressure sensor. I lean towards a clogged Diesel Particulate Filter causing your problem. I don't know much about the Cats, but on my Cummins with a DPF problem, I can do a manual regeneration to (hopefully) clear the problem up. Good luck!