AMG__Dom

Hey guys curious to see what other CL55 or even m113k owners in general are getting for MPG? mine seems to be ridiculously low even when I baby it around town, also my "after start" and "after reset" are totally off even if I start them at the same time.

My car is completely stock engine wise minus a resonator delete but even when I baby it on the highway the best I have seen is 11 MPG, around town sometimes 8-9 mpg

The car runs smooth as butter, no CEL and everything seems to be in order. This isnt my first V8 mercedes ( 210 E55, C43, 55 swapped 43, etc) I know the V8's dont get the greatest gas milage obviously, but this is just crazy considering its the same 55 motor just with a supercharger slapped on it.

Also as I stated above, on first start of the day if I reset my odomoter and average mpg the "after start" says something like 6mpg and the "after reset" was closer to 11

Any ideas whats causing this? maybe a bad MAP sensor, or is this truly the mpg we get? I know my buddy with a modded W211 E55 gets 20+ on the highway

Thanks guys! - Dom

RonCL55

My long term average mileage on my CL 55 for the last 10 years is 13. Around town I get 8 or 9. If I drive on the highway for over an hour over 60 I get 18 or 19 however if I drive over 100 I get around 15.

My prior car was an E55. It got far better mileage but no supercharger. That makes all the difference.

But the CL55 mileage is still better than my Ferrari and almost as fast��

fireman685

My recently totaled CL55 consistently achieved 20/22 mpg on the hwy. My combined city/hwy average was usually 17-18 mpg. It was an 05 Kompressor.
While driving from Flagstaff Az to Las Vegas NV it got 27 mpg but it was downhill most of the way haha.

fireman685

Reset your trip computer after you start moving, even if just rolling away from the gas station.

principledchiro

Swap in fresh O2 sensors and spark plugs.

Blkvip

when i had mine my avg was like 15-16.

AMG__Dom

Tried that this morning while babying it around and was able to hold a consistent 14-16 mpg much better than what it usually reads, wonder why

"after start" was saying 3.5 mpg at the same exact time

AMG__Dom

not too shabby! Yes, my W210 E55 definitely got better milage as well!

And hah thats awesome! pics of Ferrari!?
I'm so shocked at how cheap you can pick these up for now, so much car for the money



Swapped in fresh spark plugs a month or two ago, will give 02 sensors a try


Not bad!

fireman685

The best way to accurately determine your average mileage is to fill it up and divide the miles driven by the number of gallons it took to fill up.
You can also reset the "after start" computer when you start rolling. At a standstill it begins your average at 2 mpg. Rolling it starts around 16mpg. Straight hwy driving should yield you 20mpg easy.

fireman685

My drive from Bowling Green KY back to DFW
Round trip average from DFW to Bowling Green and back with a trip into nashvillle traffic as well.

sakodik

On my trip computer "after start" I usually get 4.5-8 MPG. Haven't seen higher than 9 in the city. I know the reason though, I usually open it up on an empty stretch cause I like the lower end torque. I am also modded and changed everything as mentioned above and more.

dblankenbaker

A dirty or bad Intake Air Temp (IAT) sensor will cause ****ty fuel economy. That's the first thing I would change.

RonCL55

So here are two mileage readouts that I took this morning. The first shows my mileage today on my drive to work today. It is 11 MPG based on 9 miles of driving, mostly city streets and a little freeway. The other is my average mileage over the last 24,000 miles which is 12.8 MPG. That is a little higher than my daily commute because it involved some highway trips.


My mileage has not really changed over 10 years of ownership. When I first got the car I was surprised at how much less mileage I got than my E55. I took it to the Mercedes dealer and they fully checked it out and he told me the mileage was "within acceptable parameters". He essentially told me the difference is "the supercharger, stupid." I will admit to trying to set a land speed record leaving every red light. Ya think that might affect the mileage a little?


However, on my best day on the highway with long trips and only going downhill, I have never got over 19 MPG.

Crissus

These cars can get much better mpg with new front Bosch O2 sensors and new IAT+Vacuum/boost sensors. I could get the car without problems in sub 10L/100km which is close to a small 4 cylinder japanese car, when going on the Autobahn and stay around 70-80mph, however my average is also 18.xL/100km which is around 12mpg. The cars power is just tempting ^^

RonCL55

Here's the 612. Yes, you can literally get these now for $200K off of original sales price. But you can also spend that on maintenance and repairs if you are not careful. I laugh when people comment on how expensive CL55 parts are!

RaceHorse

I realize its not a 55, but after some spirited driving it seems the CL 65 doesn't do too bad with the extra half liter. Not exactly sure how I managed to do this.

RonCL55

I think it is the twin turbos. Much more gas efficient than a belt driven supercharger. So you use less gas but then the big V12 gulps gas. So at the end of the day we end up at about the same place, just you get there a little faster.

AMG__Dom

Gorgeous car!

AMG__Dom

This weekend I tried to see what I could get out of her.
with truly trying driving sluggish and coasting down hills I was able to get 19.5





That was all highway driving, after some around town miles it averaged down to 15.7




Not bad at all! This is with resetting the trip while in motion, This morning I reset it at idle and without moving it said I was getting 3.5 mpg again so I'm not sure whats up with that but definitely satisfied!

RonCL55

Sounds like you are fine. Your highway mileage was equal to my best ever.

grane

The principal reason one gets a "low" mileage reading at startup is because of the MBUSA/EPA programming of the ECU. It is meant to start up rich; I used to know the exact reason why but have forgotten this CO2 BS.

The "European tune" or the "Level One" tune from some of this site's vendors, with an otherwise stock car in maintained condition, removes this restriction, should give more power and better gas mileage all other things being equal. Can any of the Forum participants attest to this?

3.5 is a good range for a MBUSA CL55. If it dips below that one has a problem. These are often caused by wear in the supercharger pulley/belt system, tensioners, etc. as much as the factors that OP have mentioned.

I have another M113 car sans supercharger. It consistently gets in the 5-6 mpg at startup despite having the nanny tune. One of the reason maybe, but this is counter-intuitive, that it is a 3 valve per cylinder version rather than the 4 of the AMG engine.

I normally get 20-22 mpg on the highway if I use the CL55 cruise control for 65-70 mph. However, even with the MBUSA nanny tune I notice that cruise control at 90 mph yields a higher mpg (93 octane Shell, Techron once a month) but I don't need any tickets.

My wife's 013 "new model" GLK 350 4x4 gets 24 mpg on the highway so I am not complaining.

RonCL55

I would love to hear from anyone that has experience on this. I would always want to get more power and better gas mileage with just a retune (who wouldn't). Would it still pass the smog? I live in the peoples republic of California and we have the worst smog rules in the nation. Also, i dont want to get into any heavy engine mods since i am happy with the car the way it is and it has 100K on it and i dont want to push my luck (though my mechanic says it is in great shape).

Thanks

grane

The problem with re flashing the ECU is that the dealer will often re-flash the car back to stock. I reckon that is for several reasons, one of which might be one needs one's TPMS system refreshed when getting new tires/sensors.
Then you have to have a system to return the car to the stage 1 or what I call the Euro tune. I don't think these are "stealth" tunes. The MB dealership will pick up on these right away. For some it does not matter since they sell nouveau-riche tuning packages themselves.

I know Euro-Charged and some other used to offer E55, Cl55 tunes and accessories such as pulleys and belt-wrap kits.

My wife feels that the CL55/65 of the 2003-2007 has a classic body style. One day people will recognize it value. I remember when you couldn't give away a Ferrari Dino.

PS
Thanks RonCL55

horiecz

E400 18mpg.. 80% city