using so much fuel I can see the gauge drop - PeachParts Mercedes-Benz Forum

minimike1 · #1 10-06-2008, 08:23 PM

My 85 300 dt is using so much fuel, I can watch the gauge drop as I drive.
Would tired injectors be a sympton of horrible fuel economy?]
this car has about 211,000 miles on it. It starts up fine, and shuts off with no lag. No a vacuum issue. And I'm thinking not valves adjustment.
Car also seems to lack a bit of power these days also.
mike

chetwesley · #2 10-06-2008, 08:32 PM

With fuel disappearing that fast, I would tend to think fuel leak somewhere, maybe up front where it will only leak when running.

Have you checked for leaks?

coonerboy · #3 10-06-2008, 08:32 PM

Have you calculated your fuel economy? I find it hard to believe that you could watch the gauge drop as you are driving unless you have a large fuel leak. Are you getting any black smoke? I know my fuel gauge tends to drop quicker from 1/2 to 1/4 of a tank than it does from full to 3/4. Fuel gauge/sending unit problem?

Also check your oil level to be sure you aren't pumping diesel into the oil from a bad fuel pump.

TylerH860 · #4 10-06-2008, 09:18 PM

300DT? What's that?

lupin..the..3rd · #5 10-06-2008, 09:42 PM

If you're loosing fuel that quickly you have a leak. If the engine were actually ingesting that much fuel, it would likely hydrolock, or at a bare minimum you'd have massive overheating.

minimike1 · #6 10-06-2008, 10:19 PM

I'll do a milage calc. but I'm sure I'm not getting 20 mpg. No leak in the fuel system, just poor economy. 300d t= 300 d turbo, just like yours. No smoke from exhaust, no overheating.

TylerH860 · #7 10-06-2008, 10:22 PM

My badge on the back doesn't say 300DT, does yours? Maybe mine fell off or something.

JimmyL · #8 10-06-2008, 10:40 PM

Quote:

Originally Posted by TylerH860

300DT? What's that?

It is a sign of amateur hour!!

Thank you Tyler for holding down the Terminology Correctness position while I've been away this evening......

I don't think anybody is ever gonna find that factory "T" on their trunk or wagon hatch anytime soon.

On a less sarcastic note {darn it} , have you figured out your actual mileage statistics during this issue? If it is truly visibly noticeable, and not just a little poetic license, then it should not be hard to locate.

kerry · #9 10-06-2008, 11:28 PM

It's a 300d-CT.

JimmyL · #10 10-06-2008, 11:35 PM

Quote:

Originally Posted by kerry

It's a 300d-CT.

Is that a 300D from Connecticut????

TheDon · #11 10-06-2008, 11:41 PM

I know that the fuel guage kind of tanks once it goes past 1/2... it drops severly on my car

from 1/2 to the next notch is like 100 miles... solid every time...

Cr from Texas · #12 10-07-2008, 12:04 AM

Quote:

Originally Posted by TylerH860

300DT? What's that?

300DT identifies the car as the 123 turbo model as there were also 300D non turbo 123 models sold at the same time. It reads 300D on my trunk lid, but the factory window sticker (yes, I still have it) says 300D-T. The FAHRZEUGDATEN reads 300 D TURBO

JimmyL · #13 10-07-2008, 12:15 AM

Quote:

Originally Posted by Cr from Texas

300DT identifies the car as the 123 turbo model as there were also 300D non turbo 123 models sold at the same time. It reads 300D on my trunk lid, but the factory window sticker (yes, I still have it) says 300D-T. The FAHRZEUGDATEN reads 300 D TURBO

Nope, you got it wrong CR. The fact that it is an '85 makes it a turbo. An extra "T" on the window sticker means some "clerical individual" somewhere entered the data incorrectly, surely counter to what the engineers and designers planned.
And whatever made the turbo the identifier???

Would an '80 300D really be a 300D-NA??? Not so much........
Always trust the trunk lid/wagon hatch!

Cr from Texas · #14 10-07-2008, 12:21 AM

Quote:

Originally Posted by JimmyL

Nope, you got it wrong CR. The fact that it is an '85 makes it a turbo. An extra "T" on the window sticker means some "clerical individual" somewhere entered the data incorrectly, surely counter to what the engineers and designers planned.
And whatever made the turbo the identifier???

Would an '80 300D really be a 300D-NA??? Not so much........
Always trust the trunk lid/wagon hatch!

I'll conceed the 85 but mine is an 83. When I've had to go the MB America for part numbers, they reply back for an 83 300DT based on my VIN. Must be the same clerk that did the window sticker in 83, LOL

Biodiesel300TD · #15 10-07-2008, 12:28 AM

I bet your fuel level sender is acting up. You can access it if you pull out the first aid kit. They get gunked up and start reading incorrectly. If it's not that then the only other explanation for being able to watch the gauge go down is a fuel leak. But you state that you don't have any leaks. So I would check out the fuel sending unit.