Dirty fuel filter
Diesel engines do not engine brake like gasoline engines do, so relatively speaking, the rate of deceleration would seem to be slower.
A deceleration valve is a device that controls the rate at which an engine returns to idle speed after the throttle is released. It helps prevent stalling and contributes to smoother engine operation during transitions from acceleration to deceleration.
Yes, a diesel engine does produce carbon monoxide during operation.
There is no such engine as a Cummins 2500 Diesel.
pree ignition timing is advanced
There are several causes for high fuel consumption in a diesel engine. These include a difference in the weight of the vehicle, increased usage of air conditioning, and a difference in tire pressure.
one of the causes is bad low quality fuel
Blue smoke is burning oil.
dirty fuel filters for one !!
You eating the engine.
unburnt fuel
The check engine light may come on during deceleration due to various issues, such as problems with the engine management system, fuel system, or emissions controls. Common causes include a faulty oxygen sensor, issues with the catalytic converter, or vacuum leaks that affect engine performance when the throttle closes. Additionally, changes in engine load during deceleration can expose existing problems that trigger the light. It's advisable to have the vehicle diagnosed with an OBD-II scanner to pinpoint the exact issue.