Heavy Fuel Consumption & Sticking in Gear

[chrisy5555]

Hello

My car has been into two different Mercedes dealerships now for

1. Heavy fuel consumption, E220 54 Plate Remapped average 22.0 mpg around the doors, no matter what i do i cant get it to be good on the fuel.

2. When you put the car into D Rive in comfort it stays in 1st gear then suddenly goes into 3rd in a harsh way.

3. Seems like at low revs its getting too much boost

I know it has been remapped but it has been fine for a year now and now its gone like this and its making me hate it

i have tried
new air and fuel filter
injection cleaner

If anything i can think of when it started was when i filled it up with optimax it seemed to go through it quickly then when normal diesel went in it seemed to continue the drinking.

any help would mean the world to me

thanks

 

[Xtractorfan]

When u say remapped do you mean on a star machine at an MB dealer or have u had it chipped /remapped on the high street by the aftermarket boys .. I would seriously consider taking it to a good indie who has a star machine

 

[chrisy5555]

well i had it remapped by the after market people has been fine for a year now.

just got it back from the dealer, I had a gearbox multiplug fitted in feb 08
since it was fitted it started sticking in 1st gear mainly when i just put it in D from Reverse it happened as soon as they fitted it I wasnt really that bothered but its been getting worse and worse so mentioned it they said they wouldnt replace it foc and they would rather strip the box down i said well i will just pay to have it replaced so i did and guess what gearbox is ok again now.

I sent mercedes Uk a complaint email asking for a refund so see what happens.
Still no further forward with heavy fuelling though
it does say on the fault sheet that the charge pressure is too high
and the air mass is too large

they didnt mention this does anyone have any ideas

i am very greatful for your help

 

[jberks]

It really is a job for either a dealer or an indie. The key question I would be asking is where is the fuel going? If it's overfuelling to that extent then you should be seeing black clouds out of the back.
Chipping does increase wear on the injectors so I suppose or two could be overfuelling. Other causes would be things that tell the ECU to overfuel so O2 sensors, MAS or temp sensor perhaps.

If it were mine, I'd be handing it to an indie specialist and asking them to sort it out.

 

[Xtractorfan]

If you had to have a multiplug fitted the seals must have been gone on the loom so its possible that the gearbox ecu is contaminated with oil..if so it needs to be cleaned and the ecu reprogrammed it is also possible that you may have been driving around in 3rd or 4th gear ..causing ur extravagant fuel consumption.. . get the gearbox ecu checked..

 

[chrisy5555]

thanks for your replys.
I took the air mass meter off my brothers car and put it on mine and its still the same.
Gears do seem to be changing alright, i did put my foot down the other day and there was a massive cloud of smoke behind me actually so maybe and i hope shes over fueling
its going back to where it was remapped this weekend so fingers crossed it will sort it out ill let you know.
thanks again guys !

 

[chrisy5555]

i have had it remapped again and still the same crap on fuel, so tried injection cleaner,
new air flow meter, air filter, checked tyres pressures etc and still crap on fuel
any more ideas guys your help would mean alot to me

 

[Paulopt2248]

Re-mapping

Hi,

The performance and fuel consumption of my C320 CDi plummeted recently and it was smoking slightly at higher speeds, so I decided to have it put on a dyno.

I did this because despite two visits to Mercedes they were unable to find what the problem was, there were no fault codes indicated. The rolling road revealed that both the power and torque figures were lower than the figures claimed by Mercedes Benz..about 5% down. The technician at 'Superchips' said he thought the MAF sensor might be the problem.

After a discussion with Mercedes....they insisted that it was not faulty, it was finally agreed that the MAF sensor would be changed. Well the results were simply amazing. The car now has its quoted BHP and torque figures and it drove better than it ever did. These figures were confirmed when the car was put on a rolling road, after the MAF was changed. Clearly the MAF sensor was the problem all along.

And after 'Superchips' installed a new enhanced file on the car it has performed brilliantly. The fuel consumption is better than it was before the car was chipped. The car is responsive and a delight to drive.

A big thank you to 'Superchips', especially Dave and Michael, for their excellent customer service and to all the chaps at their HQ for going the extra mile.

Paul