More Black Smoke than "Normal"

[travelite]

Here's the sensors on John's S60:

turbo boost (TBS)
air temperature (ATS)
coolant temperature
oil pressure
oil temperature
fuel temperature
timing reference
synchronous reference

My DD manual says this about the ATS: "The ATS provides necessary input for various functions such as varying hot idle speed, fan control, and injection timing which results in improved cold starts and reduced white smoke".

The DD manual says this about the TBS: "The TBS provides data to the ECM for use in engine fueling (smoke control)".

The way I understand it, for a particular throttle position and engine rpm, the ECM modifies its fuel delivery to achieve a particular boost pressure. If boost pressure is low, then more fuel. If boost pressure is high, then less fuel. If at altitude, where the mass of O2 is less, then more fuel, more heat, and more black smoke to achieve the desired boost pressure. If the air cleaner is clogged, resulting in less O2 mass, then more fuel, more black smoke, more heat. If the CAC is cracked resulting in less O2, then more fuel, more black smoke, and more heat.

[Gary Carmichael]

Kevin, When you speak of 12'7's are you referring to liters? MY engine is 14 liters but still, I think 500hp. Are some engines different liters and all the same HP? probably a dumb question.

[johnbrowder]

My air filter has about 5000 miles on it and looks clean.
Kevin, to be clear, I am not billowing black smoke. It is just a little puff on initial acceleration, as I continue to accelerate, I see no smoke, at a steady power setting I see no smoke. I have seen this little puff from day one with my 2003, and previously thoughout my ownership of a 2001. I just see more now than before.

From your statement, I read that ANY black smoke is abnormal. As a fleet operator, I am inclined to listen to what you say.

[travelite]

John, If you want some folks to listen to, post your question to the experts over on dieselenginetrader.com:

http://www.dieselenginetrader.com/di...es.cfm?catid=9

There are a couple of S60 techs over there who are absolute gurus on the DD S60. That's where I go for my S60 related questions. I don't own a fleet, but I think what you're seeing is normal 'altitude' smoke.

[AmeriStar]

Ok,
An initial puff of dark smoke from a cool engine is normal for 1 to 2 seconds. I guess my definition of BLACK smoke is different than dark smoke so it is probably normal.
It's our experience that dirty air filters contribute to 'smoking'. Our home base is at 4000 feet above sea level. A bus from our fleet is in Denver (5280 feet), Cheyenne (6150 feet) and Laramie (7165 feet) on a daily basis. When we see smoke, we usually have a dirty air filter.

The 12.7 litre engine is what I'm referring to when I say 12.7. The majority of 12.7's were delivered at a horsepower rating of 430/470. Increasing the HP rating uses more fuel and creates more heat and wear. Our stock 12.7's deliver a fleet average mpg, based on 2 million miles per year, of 7.1 in summer to 7.5 in winter.

The 14 litre engine is designed for 500 HP and delivers it with ease.

Just my 2 cents worth.

[johnbrowder]

We were at the end of a long day, approaching Durango, mix of up and down grades... nothing severe. I got the same beep-beep that signal low air pressure gives. I looked at the LCD display and it said: Stop, Mid 166 fault. I immediately pulled over, but did not shut down. The fault went away. No stored codes (Silver leaf), nothing visibly amiss in engine room. Looked in Prevost manual, but could not find "166". Carefully resumed journey, no issue.

Help!