Why Does My Diesel Engine Make A Popping Noise. There are several different things that can cause this to happen. Another question we get is Why Does My Diesel Engine Blow White Smoke. There are times that a diesel engine can exhibit both symptoms at the same time. First, we’ll look at what causes a popping sound in the engine. Depending on the issue in the engine you may only hear this at idle and it goes away when you rev it up or it may get louder when the engine RPM goes up. This sound can be caused by a Leaking Intake Valve, Broken Rocker Arm, or Bent Push rod. If you hear this noise in your engine it’s best to stop driving your truck and get it towed to minimize the damage to your engine. On the other hand, if your truck is blowing bluish white smoke out the exhaust it may be possible that the exhaust valve may be sticking open or the exhaust valve is burnt and creating a compression loss in cylinder. When this happens, it can’t burn the fuel in the cylinder, and it will Smoke Out The Exhaust. If your diesel engine is exhibiting these symptoms give us a call and we will be happy to diagnose the issue for you and let you know what the fix is for your engine.