Hello everyone. I need some help on where to start for diagnosising my 99 CL713's smoke issue. I need to pass my smoke test ASAP. this is my first truck and I'm still learning a lot about the buissnes and equitment so all advice is greatly appreciated. She runs good and doesn't smoke all the time. Mostly right after i shift and and when the rpms are low. But once the rpms pick up she stops smoking. To me it feels like she's dumping to much fuel but once the rpms rise and burn it off she's good. Its black smoke the truck doesn't burn oil, I'm not losing any coolant and I get good fuel mileage. A buddy of mine suggest fuel injectors and a tune?. I can afford to take it to the dealer just yet so if there's a way I can check to see if in fact I do need injectors how do I do so. I'm mechanicaly inclined and do most of my repairs but don't know much about do actual work to the motor. And another person suggested it could be a bad piston ring as well. Thanks on advance for the help
