Mario,

I concur with Vince - additives are used only when needed, not on a regular basis.

You've got some kind of problem with fuel delivery, like maybe way too much or really poor timing or something. Are there other symptoms besides high fuel consumption and lots of smoke? How's the power?

Almost sounds like someone has really over-adjusted the ALDA, which enriches fuel delivery to match the boost pressure from the turbo. Do a search in this forum for ALDA, and study up!

ALDA issue, It seems. Also, how are your ijectors? bad fuel can elad to bad injectors, and, in the long run, a few issues.

it's already time to beat this long-dead horse again?

mpavesi, run a search on this topic...you won't find one that's more contentious than this

I'll second Pierre's input of bad injectors also being a likely cause, perhaps even more likely than ALDA if no one has adjusted that. Typically an injection pump will tend toward lean as it ages, not rich. ALDA would not cause an over fueling issue if left alone.

Grey Ghost, if we can't discuss additives, how about which motor oil is best?? :D
And then we can talk about tires!

Thank you for all the info, I just finish reading about the "trailing smoke" at night, (05-2003) and thats it, I never see any smoke during the day only at night, thats great news, I am going to time her accelaration from 0-60 just in case, could very well be a little pluged after all she has been driven very soft (about 5000 per year). Thanks again for the help and I will stop with additives. I live in California I can't plug my EGR can I?

Mario

If Marshall Booth doesn't have his response (above) saved somewhere handy, I would be surprised. His viewpoint on additives is consistent and definitive.

The one thing he didn't mention was his preference for BP/Amoco diesel...

Are there any thoughts on additives which claim to increase the cetane??? Thanks

Yes, those claims are bull. Read up about additives at Chevron's website.

C'Mon Marshall.....You forgot to add the "drive it like you stole it" spiel.

Regular revving up, and highway driving will keep sooty smoke to a minimun.

The area where I live has little choice for diesel fuel. I have checked the places that carry it and they tell me the fuel is #40 cetane. My 300 SD [1993] runs fine on that, but it also leaves me wondering how higher cetane would perform.

Go to howeslube.com I have been using the stuff and like it.

My car seems to like it. The mileage went from 26 all around driving to 30 all around driving. Doesn't smoke as much as when I first bought it either.

hehe...way to go marshall.

I have been consistent about my opinion with this as well.

Once in a blue moon will an additive be needed in a vehicle that is used regularly- usually because of the ingestion of stale diesel with some H2O in it.

allow me to elaborate:

My 1969 220D ran WORSE with power service in it!

fuel economy took a sharp drop on interstate driving from 34 mpg down to 30.

injector opening became irregular during cold starts.

oil consumption increased slighly from 700 m/1 quart to 650 miles/ 1 quart.

All becuase I had a scusotmer suggest using power service.

I had to prove him wrong.

Your engine and your vehicle were not only designed to run on number one and two diesel- they become situated to it- the injectors will perform best with what they are used to receiving. The vehicle will perform MORE CONSISTENTLY IN REGARD TO FUEL CONSUMPTION, OIL CONSUMPTION AND SMOKE EXPULSION with what it has always received.

if the fuel is good, why add anyhting to it?

Pierre do you rebuild your own injectors and injection pumps in your shop?

If you could see diesels in real rough service( industrial and farm use), I think that you would change your mind about using additives. I can point to examples of equipment that was operated side by side, one using additives, and the other plain diesel. Guess which ones are still running.

The reformulation of diesel in the last few years has removed so much sulfur that diesel fuel has lost about 90% of its' main lubricating agent. Call any diesel injection shop and find out what kind of failures they are seeing with these old bosch type pumps as well as the injectors. They will tell you the same thing. Bosch is used on a large number of diesel engines. Not to use additives may have been the original recomendation of Mercedes but it seems foolish now not to. On new electronic and even late generation diesels, you will find much less of a problem because these engines and pumps were designed with this in mind.

As far as Cetane is concerned, if you don't think it is important, run it on kerosene!
Winter blend fuel is typically low on Cetane especially in the North. I have seen tractors come into dealerships in the winter and sold in the spring with Northern winter formulations of Diesel fuel still in them. Farmers have brought them back thinking something was wrong with them. When put on a dyno, they would show typically 20-30 percent HP loss (sometimes, I have seen as much as 50 HP drop in a 200 hp engine. The fuel would either be drained or Cetane added and HP would come back to full rating and fuel consumption would drop.

I regularly used Cetane booster cleaner in my 2001 F-250 and would see a 4 mpg improvement in the tanks where I used it and where I did not. In my 190 it makes a difference and I have no smoke.

I would personally recommend the diesel-kleen additives for winter, or the Lucas products. They are available at nearly every truck stop or Wal- type store.

In my last post, I neglected that most "additives" replace the sulfur with similar lubricating agents.

There is a Red Elephant in the room with this thread and some of the statements. It is that most fuel companies do blend additives to their fuels. The question should be if additives are so evil then why do they do it? Sure and engine will run on regular diesel but how well? I would liken it to using standard engine oil in a diesel or diesel rated oil in a diesel, or even synthetic oils. Cetane is one additive, and detergents are another.

Truck stops sell higher cetane fuel with additives to truckers for a reason. They need it. Although a Mercedes is a smaller version, the benefits are still there. I know Mercedes says this and Mercedes says that, but in the end any problems that are thought to be caused by additives are mechanical problems that already existed and the burning of improved fuel only exposes them (such as oil burning and other things.)

Old timers would say that if you used ether on a diesel, you would make it addicted to it. Well it was ignorance of the mechanical issues. 1) ether causes rapid upper cylinder wear, 2 it often burns out glow plugs because of the hard and quick starts they produce even while the glow plugs were still hot.

Mark: thank you for providing some counterpoint with teeth. Your arguments all make sense to me, but I'm a mechanical simpleton.

I realize that I'm just a poor country boy trying to make it in the Big City; but can someone PLEASE explain what this mysterious "ALDA" is, what it does, and whether it is found in my '87 190D 2.5 turbo? I've run a search in this forum and have still come up empty. :(

ALDA-probably an accronym for something. By and large it is for the purpose
of increasing the fuel supply as the turbo speed increases forcing more air
into the combustion chambers. Hence a bit more fuel is also needed at
the same time in order to increase engine power. Comes in handy during acceleration as well as maintaining speed when going up hill.
Regards,
Chas Mattix

Thanks for the explanation of the mysterious ALDA.

I will now put the car through a couple of acceleration tests, and I will have my tech check out the setting of the ALDA.

From the ALDA located on top of the fuel injection pump you will see
a small air line running from it. One line goes back near the firewall
to a switchover valve. Then from the switchover valve to the other
side of the engine to the intake manifold. Then a second line from
a fitting on the intake manifold to the switchover valve. Also to the
switchover valve is the + & - lines for the 12VDC current. The air
line from the intakemanifold fitting or switch connects to the negative
side of the switchover valve. The other ind is connected to the
fitting or switch on the intake manifold. It opens and closes due to
intake manifold pressure and when closed provides the ground to
the negative side of the switchover valve which permits the switchover
valve to open and close the air line to the alda.

Now let me make myself perfectly clear and say that you probably don't
understand my explanation so you may have to check those lines out
yourself. ha
Best regards,
Chas Mattix

Mr Stow, you have officially HIJACKED this thread.

Fifty lashes with an al dente noodle for ye

Au contraire, Pierre: had you been DILIGENT enough to read through the entire thread, you would have noticed, kind sir, that the number 3 entry (from the learned Mr. Dillon) CLEARLY contains a reference to the dreaded "ALDA."

Perhaps you would like to settle the matter on the squash court? ;)

I mentioned in message #28 about the various components in the ALDA
system. The reason I did is that the switchover valve failed and the
ALDA system would not work. The switchover valve is a selnoid that
permits air flow through a circuit instead of like most selnoids that
permit electric current flow through a circuit in the selnoid when it is
energized with current. The negative side of the switchover valve connects to a
pressure switch on the intake manifold that energizes with intake manifold
pressure and when it does it provides a ground path to the switchover
valve. If any of these air passages are clogged or the switchovervalve or
the pressure switch in the intake manifold is not working then the ALDA
system wil not function.
Regards, again
Chas Mattix

"incorret" appellation indeed. YOU are mistaken, Professor. There is only one (Lucky) Pierre, and I am not he.

As for the godforsaken ALDA, I think that discussion belongs in Vince Layton's cloaking thread