i went to sears and asked for a mity vac vacuum tester. no joke-- the salesman took me to the shop vac section.

thats not the point... but it make me laugh and cry at the same time.

since ill have the vacuum issues solved in short order- the last issue i really need help with is fuel economy. and not just put extra air in the tires and use power service kind of fuel economy.

the exhaust smells like fuel, it is even visible. i dont know if i am mechanically inclined enough to actually fix this problem...

my story starts like some new diesel owners do... the car would run out of gas at 1/4 tank...took the tank out and cleaned it. that fixed the problem.

i am wondering if a previous mechanic "Ramped up" the fuel to help cope with the clogged tank screen? is this normal practice among po-dunk alabama "diesel" mechanics? its getting about 21mpg lately. 90/10 highway/back road driving. i dont think this is acceptable. but i guess i am using the a/c. the car is a 79 240d. automatic. 138k. ill give it an oil change and filters soon just to do that, its not using any oil so i dont think it is oil being burned.

the smoke is just like dust kicked up, not thick enough to tell what color, really. i know thats sort of vague!

__________________
http://i68.photobucket.com/albums/i1...Untitled-1.jpg

Try a couple of things first. Try some Chevron Techron injector cleaner. This may help your injectors do the best they can. Or try some Moly Lube Diesel Purge. Adjust the valves. This will make quite a big difference if it has not been done. This should be done every 15,000 miles.
And lastly don't push so hard on the gas pedal. Its a 240D 0-60 is 25 seconds. Slow your life down and you wil get better milage.

Dave

__________________
1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car

heh heh i dont push it any harder than the guy in the yukon behind me dictates. usually 70-75

i run power service through it in every tank. i ran some sea foam through the injectors full strength about 3 months ago, its a peppy old car when the revs are right, its not a dog like it was when i got it!

my father adjusted the throttle linkage and that helped alot with the slow nature of the beastie.

my major concern is adjusting the fuel so it isnt using too much, i dont think its a driving thing. it was getting better mileage when the screen was plugged.

thats what makes me think the fuel was "turned up" to compensate for the clogged screen.

is this a mechanic repair or can i do it myself?

__________________
http://i68.photobucket.com/albums/i1...Untitled-1.jpg

I believe you are just a little confused and thinking like your diesel is simply a gass engine that uses different fuel.
Diesel engines have no throttle valve that regulates incoming air. Gas engines have a throttle to control the volume of air; but not diesels. Diesels run "wide open" at all times. Their speed is controlled by the amount of fuel injected into the cylinders--more fuel equals more power/speed. There is no such thing as saying a diesel is running "lean"--it just runs at a sloweer speed. A diesel will run as fast as the fuel it is getting, and the load on it will allow. Excess fuel is indicated by black smoke.
The thing to remember is that you control the amount of fuel ( within limits) by your right foot. If you see a little smoke, back off the accelerator a bit.
The reason that you were getting better mileage with the plugged screen is that the plugged screen was limiting the fuel supply to the engine. Now, with that restriction gone, you must limit the fuel. In effect, it is you who have turned up the fuel supply.
If your car starts quikly in all weather, then you can assume that its internal condition is OK. Do the maintenance items above and drive as gently as possible. While a 240D will reach speeds approaching 90 mph, it is far happier at lower speeds. 75mph is too fast for good economy.

the above. the mileage is not that far off. use good fuel, keep the filters clean, all three, air two fuel, and keep the oil changed. the fuel can be adjusted but i doubt it will affect mileage much. it will affect performance though. a noticable amount. any competant diesel mechanic should be able to adjust the fuel.

__________________
[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.

alright-

thanks yall!

so a little smoke isnt much of a concern? it does smell like fuel, some lady at burger king asked me if it was safe. heh heh

i guess in the fall ill take it to the benz mechanic in town and ask him to inspect it. that is the worst thing about living in a state with no automobile regulations other than it being able to roll under its own power!

im sure AlDiesel can chime in here! we have some DANGEROUS cars on our roads, cars that if hit again, could kill all passengers in a very light impact. we're talking about hyundais with no bumpers and bungee cords holding them together. its scary stuff!

__________________
http://i68.photobucket.com/albums/i1...Untitled-1.jpg