How blocked will the lines be to cause an issue, and what do I use to clean them?

If the line from the manifold is choked with carbon, it won't send pressure to the ALDA and you won't get fuel enrichment.

You can blow them out with some compressed air and some Brakekleen if you have it. Don't get the Brakekleen in the overboost protection valve. The plastic may not like it.

Pay careful attention to the banjo bolt on the back of the intake manifold. I has a tiny passage through the center that must be clean.

what is a lot? and what does it matter if it is only above 3500 rpm?

tom w

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

A lot means that I can leave a black stream behind me! It is much worse than my IDI ford. And it is over fueled.
And if it only happens above 3500 it may not be an issue. But the car is new to me, and I am trying to find what is normal, what is not, and why. And repair it.
It soulds like it may be a sign of a clogged line that is also causing the car to be weak in the cold morning.
I want the car to run well. It has to be my daily driver, and I need the best milage I can get from it.

I will check the bolt also. and clean the lines listed above.

thanks.
Doug

Understand that the two issues are not related.

The clogged line would result in a condition that provides too little fuel and the vehicle feels sluggish.

The black smoke is an overfueled condition, which, if I had to guess, would make the clogged line scenario be highly unlikely. I'm doubtful that you can get that much fuel into the engine if the ALDA (fuel enrichment) is non-functional due to a clogged line from the manifold.

Assuming he's talking about a steady 3500+ rpm, you shouldn't be able to see any smoke in the mirror (even at night). Hard acceleration above 3500 is a different matter. In my 300D, 3500 rpm is only about 80 mph. I routinely set the cruise at 3500+ for several hours at a time. Aside from being less than aesthetically pleasing, black smoke would indicate significant extra fuel being burned.

Could the car being slightly sluggish in the morning for a few minutes also, in part, be due to the molasses-like consistency of 15w-40 motor oil when cold? I've been told this is a possible reason as well...

oh yeah, is see you live in colorado. it seems like out west you can drive a lot faster than in the midwest. i seldom cruise at over 3500 rpm with the sdl with the 2.88 rear. seldom over indicated 80 mph which i believe would be maybe 3300 or so.

but at that rpm i would expect some smoke that would be visible mostly at night.

tom w

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Good point, I have 3.07 gears so I use a few more rpm's. Most of the interstates have 75 mph speed limits (away from the cities), so if you drive at anything below 80 your likely to get run over by a BIG truck (which makes driving the 240D interesting ). I really don't see smoke under steady conditions, just a puff sometimes at the bottom or top of a hill if the cruise control over-reacts.