Black smoke on acceleration (more than normal)

[MHowell]

2003 HO, 2500, 4x4 150k miles

I have recently noticed a significant increase in black smoke under moderate to spirited acceleration above 2000 RPM. I have never noticed THIS much smoke before. I haven't changed anything, the entire truck is in stock form.

It is slightly overdue for an oil/filter and fuel filter change.

It does this whether the engine is cold or hot.

What could be the cause of what seems to be an excessive amount of smoke under load like this?

 

[KFranco]

As you said, first check your air filter for blockage and that your're getting the most unrestricted air supply. Next check for boost leaks. Your sig indicates no gauges. Knowing that you're getting enough boost at the rpm's you're having a smoke issue would help rule out any turbo/boost problems.

 

[MHowell]

No guages. The air filter looks dirty, but not overly dirty. I'll change it and see if that helps.

Can a bad tank of fuel cause this? I just filled up recently, but that could be coincidence.

 

[KFranco]

Can't really say. I've never had a bad tank of fuel or heard what it does. My inclination is that a bad tank of fuel would make your truck run poorly if at all and that doesn't seem to be the case. Either you're not getting enough air/boost or for some reason you're dumping too much fuel into the combustion chamber with the correct air/boost parameter for a stock truck. If you can confirm that airflow and boost are being met then perhaps you have a bad injector or injectors.

 

[MHowell]

OK, before we get too deep into this, I'll change the air filter (as well as the oil change/filter and fuel filter) and see if that helps.

Thanks for the info.