Ellton

Hi All,

Recently I have noticed a much higher fuel consumption on my 2011 S350 BlueTec.

The overall range dropped from a maximum of ~1300km (long range) ~ 1000km (city and long) on a full tank to around 700km city and long.

My average fuel consumption seems to be 14.2l/100km which is simply unbelievable.

Had mentioned this to the service centre but the person in charge assured me that everything is fine after running readouts.

The only notable events I can think of that came up during the last 2 servicing sessions were a faulty NOx sensor during the last servicing and the service guys not leveling a tire / brake properly which in turn led to a tire and break wearing out much faster than it was supposed to. This was done at a much earlier servicing and only corrected on my last service after they tested the wear levels on the breaks + replacing the tires.

It seems to me that the first 3-4 gears seem to be eating up 18+ litres /100km when the acceleration is used. It then drops down to a steady 4-5litres/100km whilst driving 50km/h. At this point I do not even know if this is normal behaviour as my head is completely spinning. Reaching speeds of 170km/h I at times seem to be using 11 litres /100km.

Unfortunately I have no clue what could cause this issue and am wondering if anyone might suspect something based on experience.

alx

Start the car cold. Drive around suitable route so you don't brake. You don have to drive fast. 40-50km/h for 5-10 minutes is ok. Come to a stop trying to not use the brakes. Uphill works well. Get out of the car and carefully check brake calipers. One is significantly warmer than the others? That one is stuck and dragging the pads reducing your fuel economy. Obviously use caution- if sticking a caliper might be very hot.

This assumes that your tires have the correct pressure, and the car is properly aligned. Note that some tires do have higher rolling resistance and simply will result in higher consumption.

My guess is if you have seen such change in consumption you have a sticking caliper or two.

NickPoint

Hi! It's been a while since you asked for help, but I have precisely the same problem with my W221 4MATIC 350 BlueTEC. Do you remember by any chance how you fixed it? Any information would be helpful for me. I know that my car has a disabled AdBlue system and also throws a 12BC00 error (Component B28/8 Differential pressure sensor DPF has a plausibility error) from time to time. However, when I look at real-time values, they show within an acceptable range.

BOTUS

my earlier v8 and a mate with a CL550 both had fuel consumption fall off a cliff in last 18 months (20% increase)

I'm baffled as to why, but three things all impacting it

google (using spyware free mapping) together with the local authorities in the last 10 years have destroyed the UK road network - we now have most sections of key roads altered with road calming drivel, re timed traffic lights etc. so where once a road flowed, now we have multiple silly pointless bottlenecks. Where its not viable to place these on more open roads, we have thousands of fake roadworks controlled by traffic lights - they sit for years with nothing other than road debris building around sandbags holding the lights and signs up with no physical maintenance happening - this means the cars is usually operating only between 600 and 1300 rpm for 90% of any trip

ethanol has a far lower power density than real petrol - so the criminal corps can sell vastly more of the dangerous filth. At 10% ethanol in the fuel we must get a 6% reduction in economy - but with further magic they have created a fuel that seems closer to the 20% loss I see. My bikes are also impacted dramatically. Ethanol by the way uses far more energy to create then refining petrol - so its a double whammy for the planet - just as they were ordered - vandalise the planet much faster so with can reach the Zionist end game on their timeline)

does aging CAT sensors create a trigger signal that leads to over fueling by the Bosch ECU ? This seem to be a real unwanted effect. One factor suggesting this is where Bikes run so lean they are often dangerous to ride slowly round town, coughing and trying to stall as you want to use engine power to help your balance. So many try to address with gadgets. The best an American AF-Xied device sits inline with the CAT sensor and manipulates the signal the ECU sees, thus richening the bike till it runs correctly. But the manufacturers says they only work with "a strong signal from the CAT sensor". Mine have only done 70K - and reading Merc documentation, it pretends they are meant for 250k miles - but fuel use is horrific nowadays and the bike killed a Bosch cat sensor at 37k last summer - we need to remember modern vehicle manufacturers spend billions on alchemy and thus time is the main killer, not miles

BOTUS

wow is this thread about tractors ?

its well known for them to keep injecting tractor fuel where most ends up in to the engine sump when a sensor has gone wrong on the DPF.... as of 6 years back a 5th gen temp sensor still wasn't working - I believe with that lying it fails to set the DPF on fire and so keeps flooding the thing with fuel in the hope one day it incinerates all the cancer its collected

check the engine oil level and either sort the DPF system, or at least change the oil so it has engine oil lubricating the engine rather than 50 50 tractor fuel and oil


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