I have ML270 AUTO which is only doing 12mpg. I have had the EGR cleaned and a system check. Will a Star diagnostics check show what the problem is.

[keithmerc220]

I have a ML270 it is only doing 12mpg. I had the EGR checked and machine cleaned. Still no better, will a full Star Diagnostics show up the reason?

 

[Smart320]

Not if the petrol tank is leaking

 

[DSM10000]

Not if the petrol tank is leaking

EGR and 270 equals Diesel

 

[DSM10000]

I have a ML270 it is only doing 12mpg. I had the EGR checked and machine cleaned. Still no better, will a full Star Diagnostics show up the reason?

How long have you had the vehicle?

What sort of driving are you doing? City, towing?

Does the vehicle temperature gauge get into the high 80's C?

 

[Riva811]

Check if the recent recall affects it, water goes in the rear, messes up fuel pump and wiring

 

[keithmerc220]

How long have you had the vehicle?

What sort of driving are you doing? City, towing?

Does the vehicle temperature gauge get into the high 80's C?

Hi
Mostly around 10 mile trips rural driving, I have just done a 22 mile 70mph dual carriage run and it returned 11.7mpg
The temperature gauge showed 82 degrees.
I have just had a professional EGR clean and diagnostic nothing showed up on the diagnostic.

 

[DSM10000]

Hi
Mostly around 10 mile trips rural driving, I have just done a 22 mile 70mph dual carriage run and it returned 11.7mpg
The temperature gauge showed 82 degrees.
I have just had a professional EGR clean and diagnostic nothing showed up on the diagnostic.

Where are you getting the mpg figures from?

Do you know what device was used on the diagnostic scan?

The only accurate way is to brim the fuel tank, drive for a couple of hundred miles, brim it again and then calculate the mpg.

If you are burning that much diesel there would be a lot of black smoke.

 

[jasonh]

Yes diagnostics should help. Something is definitely not right. But you need someone who really knows what they are doing. Generic diagnostics should pick up engine related faults but maybe not your problem.

Find a Mercedes specialist nearby, not a main dealer.

As DSM10000 has suggested if the thermostat has failed the car may be running cold and then it will guzzle fuel. That won't show up as a fault - but someone who knows what they are doing should spot it.

 

[m80]

Are the wheels (well brakes) hot?

 

[91dm]

Has the jeep full power, does the turbo seem to be boosting and you can get up to normal speeds?

I'd check the MAF first and if there's any black smoke on acceleration check the intercooler pipes for leaks.