ISL9 Problems

[schISM]

Try disconnecting the intake tract right at the intake manifold and see if that solves the excessive smoke. Cummins utilized an intake air throttle on some models, not sure if the ISL had such a contraption. Ya gotta solve the smoke issue and if the fuel side is doing what it should then it's not getting enough air. Maybe the customer replaced the air filter during the "service" and left the plastic wrap on. You'd be surprised what people do.