Mercedes-Benz Forum banner

1 - 10 of 10 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter #1
We recently picked up a 2001 E320 Wagon (not 4-Matic). The highway mileage is OK (about 27 mpg) but the city mileage is horrendous (about 9-10 mpg). The car seems to be running fine and I know the MAF is new because the dealer changed it for us when we bought the car and a fault code went off shortly after that.

I know what I would do if the car was a '69 Buick but where do you start with a car where everything is controlled by computer? Are there problems common to the W210 models that will lower your MPG but not throw codes?
 

·
Registered
2005 W215 CL500
Joined
·
3,583 Posts
Awful. I go an indicated 51.7mpg last week over 120 miles. It was snowing and I was restricted to 50mph.
 

·
Registered
'02 E320 4matic Wagon
Joined
·
326 Posts
I get upset when it dips into the teens.... yours is bad.

Where do you live? I wonder if your car is not warming up properly with the local driving and running rich.

I would say use some Techron to see if it helps, but yours is so bad, there must be something major wrong.
 

·
Registered
Joined
·
4 Posts
Discussion Starter #4
Well it has gotten cold and my wife does take mostly short trips (<10 minutes) but 9mpg? The engine is a 3.2L! I always thought you had to have a 6.0L V8 or larger engine to dip into the single digits.

The oil has recently been changed and the MAF is new. If no codes are being thrown, could it still be an O2 sensor? Or is it more likely to be a plugs/wires/fuel filter/air filter issue? I'm willing to try anything since we're going through 20 gallons a week driving less than 200 miles. That's insane!
 

·
Registered
1999 E55, 2001 E320, 1990 560 SEC, 2004 ML350, 2001 ML55, 1995 S500, 1998 SL500, 2010 E550 Sport zoo
Joined
·
7,035 Posts
My personal opinion - I agree it's a horrible situation, and unfortunately the car was a recent "dealer" purcahse which throws the history of the car as suspect.

I would run thru the basics, to see if the affordable changes there can improve the situation:

a) ECU reset
b) ask the "dealer" how/who he sourced the MAF, that MAF if generic or non-brand could be a issue
c) pull a spark plug to check condition
d) $16 for a fresh air filter
e) run a bottle of fuel treatment (large bottle of Techron) into the system
f) MOST importantly - have the cats checked, you might have a boogie in the cat system
g) find your most affordable option to have a full SDS scan run
 

·
Registered
'02 E320 4matic Wagon
Joined
·
326 Posts
Did a little checking today. It was in the upper 20s and I took the car out for just a local stop and go. It was 2 miles of driving in about 10 minutes and my mpg stated 11. Then I drove onto a more open road and the milage counted up quickly once everything warmed up.

If you are just driving <10 minutes and only a few miles, I guess it is possible to have that low of a mpg. How about just doing a few more miles on a 40-50 mph road to see if it starts to climb?
 

·
Registered
1999 E55, 2001 E320, 1990 560 SEC, 2004 ML350, 2001 ML55, 1995 S500, 1998 SL500, 2010 E550 Sport zoo
Joined
·
7,035 Posts
Wagonz you are going to drive yourself crazy using the onboard readout to check mileage on 2 miles trips over terrain - it at best is a tool used to measure overall/average MPG over extended intervals, it is of no value over short "trips". Same applies to onboard MPG computers in other cars outside of MB.

Keep the faith !
 

·
Registered
'02 E320 4matic Wagon
Joined
·
326 Posts
Right, that is why I was asking if he puts some more miles on it, does the mpg climb. With the built in calculation, the more data it gets over time, the more accurate it is.
The low mpg he is seeing may be "normal" based on the display. No need to throw parts at the car then.

Wagonz you are going to drive yourself crazy using the onboard readout to check mileage on 2 miles trips over terrain - it at best is a tool used to measure overall/average MPG over extended intervals, it is of no value over short "trips". Same applies to onboard MPG computers in other cars outside of MB.

Keep the faith !
 

·
Moderator
93 SL500, 95 SL320, 96 S320, 98 S500, 2002 E320 4Matic Wagon & A little 91 5.0 FORD Mustang
Joined
·
8,064 Posts
Check you thermostat?

I could be stuck in a open state...

When you have a good thermostat the car should warm (temp gauge) up quickly.

If you change it out, boil the new and old one. The new one should open and close quickly. Now, both are working properly. then your problem is somewhere else.

Martin
 
1 - 10 of 10 Posts
Top