glc mpg problems

[cataloyking]

has anyone had issues with mpg on their glc models I am having problems with my c220glc initially getting anything between 48 to 55mpg then it dropped to 29 /31mpg main dealer say nothing is wrong with it then my management light came on then the check ad blue light came on merc took it in and said it was the ad blue injection that was the problem which they repaired the 1st 2/3 weeks the mpg went up to between 48 to 55mpg then it has dropped to 29/31mpg the onboard computer confirms this I am about my wits end with this can anyone throw any light on this thanks in advance

 

[LostKiwi]

Take it back to the dealer. Something is clearly not right and it's their responsibility to fix it.

 

[cataloyking]

Take it back to the dealer. Something is clearly not right and it's their responsibility to fix it.

 

[cataloyking]

thanks lost kiwi for your reply it is going into main dealer on the 21st I wont hold my breath they say that is all I will get mpg wise but I beg to differ they told me to run the fuel down until the light comes on then refill the fuel and see what mpg I get this I have done but there is no change mpg wise so don't know what they will come up with now the on board computer says the same as I worked out tank to tank very strange I will come back with an update when I get it back thanks

 

[ThinkPad]

Have had a GLC from new. 250d but same engine. We have averaged around 32mpg. Over 27000 miles.

Most of that is around town but haven't seen much above 40mpg in any type of driving.

Not sure how you were getting in the 50s...I assume you nannied it?

Sent from my SM-N950F using Tapatalk

 

[Srdl]

LostKiwi is right, of course. Something is not right and it is up to them to correct it. You may have to make a nuisance of yourself and cause a fuss because the dealers standard responses are usually “it’s normal”, “they all do this” etc. But they don’t like customers causing a fuss in front of others so you may need to get cross with them in the showroom.

I know everyone’s driving style and journey profile is different but you know what is normal for you and you knew when something was wrong before. Supposedly they corrected this but that problem or a similar one has recurred.

ThinkPad has given you his experience but here are a couple of other examples. My sister has a GLC250 Petrol and can get 35mpg on a run, a bit less around town, and she is not a slow driver. I usually expect between 27 and 30 (have had 31) on a run out of my “proper” AMG and that’s with a 3 litre, V6, twin-turbo petrol. We don’t use it much for town driving.

Your 48/55 sounds a little optimistic but you should be seeing much better than 29/31 - so don’t accept “no” for and answer and stand your ground. Good luck!

 

[ajlsl600]

thanks lost kiwi for your reply it is going into main dealer on the 21st I wont hold my breath they say that is all I will get mpg wise but I beg to differ they told me to run the fuel down until the light comes on then refill the fuel and see what mpg I get this I have done but there is no change mpg wise so don't know what they will come up with now the on board computer says the same as I worked out tank to tank very strange I will come back with an update when I get it back thanks

take it back and leave it there until it returns to former mpg or they explain in writing the reason for the big differences . something wrong with regen system ? assume thats on this car ? the cynic in me says warranty coming to end and fannying started ??

 

[cataloyking]

thanks for all the replies I will post back when they look at it next week

 

[mancman]

I’m getting around 38-42 on motorway doing around 70mph

 

[bembo449]

I regularly get over 30mpg from my insignia vxr and its 4wd and rocking 400bhp so there is most definitely a problem with your GLC but your going to have to keep nagging MB to sort it , main dealers love nothing more than fobbing folk off , id wager they know there is an issue with the ad blue / DPF set up that effecting the cars economy a bit like the front tyres skipping across tarmac that was never a problem either on the GLC

 

[EmilysDad]

I regularly get over 30mpg from my insignia vxr and its part time 4wd and ....

FTFY

 

[bembo449]

FTFY [/QUO
its 550 quid a year to tax , its full time 4wd !

 

[EmilysDad]

its 550 quid a year to tax , its full time 4wd !

My apologies then .....

 

[bembo449]

oh accepted , its the only real bug bare I have with the car but as it replaced my 216 I can hardly complain

 

[EmilysDad]

oh accepted , its the only real bug bare I have with the car but as it replaced my 216 I can hardly complain

VED is a shambles. My R320 was in the £500+ band whereas my ML350 is around £300 and is basically the same engine but with ADBLUE
My Smart Roadster is 700cc and is £150? but the Smart 451 is 1000cc and is £30 a year .... manufacturers just manipulated emission figures to suit ....

 

[Blobcat]

VED is a shambles. My R320 was in the £500+ band whereas my ML350 is around £300 and is basically the same engine but with ADBLUE
My Smart Roadster is 700cc and is £150? but the Smart 451 is 1000cc and is £30 a year .... manufacturers just manipulated emission figures to suit ....

On this I don’t blame the manufacturers, they were just working with the rules they were given. By testing in ideal conditions and reducing the required emissions meant cheaper VED for consumers.

 

[umblecumbuz]

Are you resetting your computer on each fill up?
I have one car that annoyingly resets the consumption reading whenever I fill with fuel. Although it averages out over a tank full, it gives me a false reading for a while before it settles.

Would this be your case also, giving you an inflated reading which subsequently becomes the norm?

 

[ajlsl600]

none of the results are from real time driving and therefore useless info.. the only way is to glean this info from others before you leap and sign the purchase papers. after which, unfortunately one is at the back of the priority list ..

 

[cataloyking]

thanks lost kiwi for your reply it is going into main dealer on the 21st I wont hold my breath they say that is all I will get mpg wise but I beg to differ they told me to run the fuel down until the light comes on then refill the fuel and see what mpg I get this I have done but there is no change mpg wise so don't know what they will come up with now the on board computer says the same as I worked out tank to tank very strange I will come back with an update when I get it back thanks

 

[cataloyking]

ust an update on the mpg on my glc main dealer had my car for 3days and they ran it but came back saying they cannot find anything wrong they were getting anything between 31/37mpg with it and could do nothing more with it not the result I was needing so will think again about replacing like for like