Lots of things can affect MPG... I'd start with the obvious, like new fuel & air filters. Wouldn't hurt to check the tranny & diff fluid levels, and/or replace the fluid if due. Next up is dragging brakes (wheels should spin very easily), low tire pressure, fuel leaks somewhere (don't forget to check back at the tank & lines), engine temp too low (t-stat), bad alignment, and some other things I can't think of offhand.

Wheel diameter.

Sixto
93 300SD

I got the ALDA off. It was a little tougher for me since I have a flat plate heat exchanger in that nice open spot where the wrenches would normally fit...
1-1/16 and a 24mm worked for me.

I'm taking it out with me tomorrow to try to find a nipple and cap, or a plug, that will fit over the hole.

I also need a 12 mm deep well socket to get the #1 glow plug out. I know I own one. I just have not seen it for years...

My boost pressure sensor was completely clogged. (Not the fitting that goes over to the ALDA.)

I broke one of the linkages to the, heck I don't know what it is, I guess the throttle. I'm buying 2 right hand thread and 2 left hand thread. If one can snap, so can the others...

-Jim

__________________
1995 S350D, Green with black leather interior.
Bought January 2008 w/ 233,xxx miles.
I did 22,000 miles during the first year of ownership.

Is the throttle even needed if the EGR and air recirculating valve are disabled?

__________________
Ron Schroeder
'85 300 Turbo Diesel 2 tank WVO
'83 300 Turbo Diesel 2 tank WVO
Some former WVO vehicles since ~1980:
'83 Mercedes 240D
'80 Audi 4000D
'83 ISUZU Pup
'70 SAAB 99 with Kubota diesel
'76 Honda Civic with Kubota diesel
'86 Golf
Several diesel generators
All with 2 tank WVO conversion
LI NY

How else is fuel increased?

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I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG]

I think he's referring to the "throttle" plate in the intake manifold that creates some pressure differential for the EGR to work. My 240D had one, I removed the linkage and the flapper when I disabled the EGR.

On a W115, the "throttle" needs to be there for the engine to run properly.
On a 240D, if you disable the EGR, then you can remove the butterfly valve and associated linkage.

Ah okay.

__________________
I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG]

Heck, I don't know what it is. It's broken. I've ordered the new parts.

http://catalog.eautopartscatalog.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.peachparts.com/&cookieid=1X80RQC8N1XI0OWE2V&year=1987&make=MB&model=300-DT-002&category=All&part=Throttle+Linkage+Socket

"Throttle Linkage Socket" Brittle plastic after 20 years.

-Jim

__________________
1995 S350D, Green with black leather interior.
Bought January 2008 w/ 233,xxx miles.
I did 22,000 miles during the first year of ownership.

after reading this 10 page post, the ALDA is coming off the 87 tonight. I do have more concern that this will help the 82 CD more though, its become quite a dog lately. I had gone junkyard shopping and got a virgin ALDA off an 85 low mileage 300D but it only made the car run slower with it maxxed out. It threw the shifts off too as decsribed a few pages back.

I still have my ARV plugged in on this car, so am I to understand the line can be removed and capped at the ARV and the switchover valve behind the headlight too?

I've been following mpg too on the 87 for the last 2 tanks. first was ~23MPG with untouched ALDA and second was ~22MPG with it backed out 1 turn (1/2 turn to max left). A little disapointing. I did fuel filters about 2 years ago, but the car sat unused for about 3/4 of that period. what do you think? Change them again anyways?

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1980 500SE/AMG Euro
1981 500SEL Euro
1982 380SEL
1983 300TD
1983 500SEC/AMG Euro
1984 500SEC
1984 300TD Euro
1986 190E 2.3-16
1986 190E 2.3
1987 300D
1997 C36 AMG
2003 C320T 4matic

past: 1969 280SE 4.5 | 1978 240D | 1978 300D | 1981 300SD | 1981 300SD | 1982 300CD | 1983 300CD | 1983 300SD | 1983 380SEC | 1984 300D | 1984 300D | 1984 300TD | 1984 500SEL | 1984 300SD | 1985 300D | 1986 300E | 1986 560SEL | 1986 560SEL/Carat | 1987 560SEC | 1991 300D 2.5 | 2006 R350

Yep, all vacuum plumbing to the right side of the vehicle can be eliminated.

On the W126, I replace the four way connector above the vacuum pump with a two way "F" connector. Everything that went off to the right side is trashed.

Of course you are operating your vehicle off road only, correct? I have seen three EPA roadblocks in Southampton this week. The inside scoop is that they are looking for missing ALDAs.

__________________
Doug

1987 300TD x 3
2005 E320CDI

........of course.........an SDL makes a great off-road vehicle........

Fuel and Air Filters are new. Tranny and Diff fluid were changed at 260K, brakes are not dragging, right rear tire pressure was very low (found a nail), no fuel leaks, all new lines, checked again, thermostat is new, temp gauge sits right above the 80 line. Alignment is dead nuts on......

On a higher note, the car got 23.94 mpg this tank, driving like a human being this time, not WOT and making it smoke with no ALDA there. So I'm pretty happy with it. We'll see what happens with the tires at the correct pressure.

__________________
91 350SD
14 F150 Eco
19 Fusion Hybrid
11 GT500

Hmmm... 24mpg is better. It's still low, but at least you're in the ballpark now. For grins, what's the chain stretch, and IP timing set to?