Two full turns back on the screw adjustment on the ALDA is what it took to gain my missing power. The car is a '93 300D. I have heard of 1.5 turns being used for an extreme case of lost power, but mine was apparently that bad. Amazing to think that it very likely went all of its 126K lacking so much power. It is a relief to finally ne able to hit the gas pedal and move with the A/C on. The damn thing was so slow before that we would have to turn off the A/C while we got up to speed.

The performance is dramatically improved, but I thing its got a little more to give. The boost does not feel like it is close to spec. I will have to make the pressure (boost) guage setup to confirm my suspicion.

Thanks to Dave Miemann, and all who helped.

Just a little side note, I was disappointed to find that the ALDA on my '93 is not rebuildable as the older (eg, like my '87) type shown in Dave M's procedure. It was a relief that it was not necessary.

-Neil

__________________
'01 CLK430 (hers)
'99 528iT (turd)
'87 Porsche 928 (just for fun)

You may want to verify that you are actually getting boost before leaving the ALDA set that high -- if the EGR isn't working due to a leaking hose or bad actuator, the computer will shut the boost off, leaving you with a VERY slow car. You can overcome that to a certain point by richening up, but you then risk overheating and partially plugging the catalyst under the floor, and you will be back at very low power, this time from excess back pressure.

If you restore the boost, readjust the ALDA, you may be very rich when you get boost.

Don't forget to check for plugged lines and a blown overboost controller, or a bad boost control servo and/or actuator, I think the are vac operated on your car. Make sure the actuator hold vac -- if they leak, no boost!


If you have disabled the EGR, you will have to hook it back up -- the computer "knows" when it is working, I think and cuts the boost off. Big pain, but then, why screw around with it?

Good Luck!

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

Mespe,

http://engine.mbzarticles.org/diesel/alda/


Psfred,

Thanks, I actually have tackled that part of the turbo issue. The EGR had been almost completely clogged up, prompting the computer to do exactly as you said. I pulled out enough carbon to be about the size of a golf ball. The isseue I am referring to is the fact that there seems to be boost prestent, just not much. It helps that my mother has the same car in good tune so that I have a basis of comparison (on the occasions that I make it out to Florida). The EGR now seems to be working as it should.

Where is the "catalyst under the floor"? Can it be serviced or is it a replacement only item? If my EGR was that badly clogged, then this may be clogged as well...

__________________
'01 CLK430 (hers)
'99 528iT (turd)
'87 Porsche 928 (just for fun)

Catalyst is the first "muffler" in the pipe under the car. Non servicable, very expensive.

Make sure the pipe going into the manifold from the EGR is completely clean, and that the EGR valve itself is clean -- doesn't take much to plug it up internally.

I would find the problem with the boost from the turbocharger -- I believe (could be wrong) that it isn't particularly simple, but at the very least I would check the operation of the vacuum actuators for the boost controller and the EGR, as well as actual operation of the valves -- EGR must move, both open and closed, upon applying and releasing vac, and the wastegate control for the turbo must move as well. I don't knon what kind of wastegate control you have, it may not be obvious in operation.

Once you get the boost restored, recheck the ALDA.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

Thanks. I know I got the EGR pretty well cleaned and functioning properly. I have not checked vacuum operation on the turbo yet, but I have noticed that the wastegate rod looks to be very easy to adjust. I am sure that further alda adjustment will have to be done if I do adjust the turbo.

Is there a way to check the "first muffler"?

__________________
'01 CLK430 (hers)
'99 528iT (turd)
'87 Porsche 928 (just for fun)

Hey,

What do those burning file icons next to the subject mean? Hot topic? Eyes only (burn this when you read it)?

-Neil

__________________
'01 CLK430 (hers)
'99 528iT (turd)
'87 Porsche 928 (just for fun)