Brief history: 1989 300te, purchased from my mechanic several months ago... all new valves, head gasket done before it left his shop. State inspection/ exhaust meter readings show mixture to be dead on!...fuel milage stinks: 15- 19 mpg. Not what I expected from this car. Car runs super great. Running Mobil 1 oil, using high grade fuel. Mechanic says the O2 sensor is working properly.
I feel that I made the wrong choice in cars, now. This thing is eating up fuel and my wallet.

Where do you live? The colder weather causes more fuel consumption. I used to get about 14-16 mpg in my '85 280SEL with winter.

I'm only driving diesel right now, and my mileage has been about 22-23 mpg steady from New England.

My sister's '88 300TE gets about 22-24 mpg in the summer. I can't even imagine what a 560SEL would be getting.

How hard are you on the pedal?

1990 300te 4-matic 16-19mpg. Always been that way for my family.

What type of driving do you do: city, highway, combined?

The 3.27 diff, IMHO is too much for everyday driving. Go to a 3.07 or 2.87 diff and your gas mileage won't be as bad.

The downside, is that acceleration will be slightly down, unless you manually shift down for a 1st gear start when stopped.

:-) neil
1988 360TE AMG
1993 500E

I think the Munroney sticker on the car claimed 17 city/21 highway. My numbers might be off a bit, but it's none too impressive mileage. Depending on your driving style, trip length, gasoline oxygenation, etc. you might be about right.

- JimY

My MPG sucks also I get barely 21 MPG on the highway, i have a 97 c280 with about 90K on it. My friend told me to change my O2 sensor and the MPG should improve a little. What you guys think???

Eliot: I have a 2.87 diff for sale if you're interested. $125 and it will bolt right up to your 1989 300TE.

:-) neil

21 mpg is not that bad for a C280, especially if you do mainly city driving. It does seem a little on the low side, and I'd look at replacing your spark plugs.

A bad O2 sensor will cause your mpg to plummet really, really low, like in the low teens.

__________________
Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".

Is O2 sensor DIY? Any special tools required?

Very easy job, just disconnect the harness under the front passenger carpet and slide a box-end wrench over the wires and around the sensor.
There are Bosch generic sensors available for much less than factory, (**************.com) but you need to solder the wires to the terminals before installation.

Good luck

__________________
1939 170 - till I was 3, still turns heads
1989 300TE - daily driver has 263k
1987 300E - purrs happily with 120k
1983 300SD - keeps my friend happy

might be that 4matic system. I can pull 23mpg out of my 300SE (3.46 rear end) doing 80mph. City I get around 17.

Is your fuel system functioning properly? Duty cycle readings? Deceleration shutoff switch kick in when foot is off gas?

__________________
'90 300SE 298k
-300K and it gets put into retirement.
'80 300D 255k Purchased new by family in 1980.

Had a:
1973 220 (gas)
1980 300SD
1992 400E

Tire pressure and type can also be checked.


I have 25/19 with average of 22Mpg (1,07liter/10km)
Fuel cut off is important ,check connection of the switch.
Also check for leaks with some starting gas.



Pelle

300E 4M -89