When accelerating there is black smoke coming from the exhaust

Hi Kirk,

More than likely you have an issue with the EGR valve. A natural byproduct of a diesel engine is soot. The EGR system unfortunately gets jammed up and does not function properly. Once this happens you will actually get a loss of power potentially and black smoke.

I would recommend remove the valve and inspect the rubber hoses and hard lines connected to it for excessive soot. There will be some but it should be a fine dry dust. If the valve has too much then you can clean it using a chemical made for this that you can get at a parts store.

This is the most likely cause so I would inspect this first and go from there.

Okay. Did you find any soot in the EGR and did you replace the valve?

When the engine is off the valve should be closed. Here is a video that shows this. It also shows what acceptable soot looks like.

https://youtu.be/bl20p-aaM2c

If you have wet soot then you may have injector issues. If this is the case then replacing the EGR (assuming it is stuck) will not permanently fix your issue. What happens is the injectors start over fueling and this causes excess soot to build up in the EGR system. If the egr is working properly, I would find a heavy diesel injector cleaner that you can add to your fuel tank and see this this will help with the smoke issue. If not, I suspect the injectors are the issue. However, a stuck EGR explains the smoke more than injectors but if that proves out ok then I would look at injectors next.