Excessive fuel consumption on 2003 w211 e270

[RUBBER_UNDIES]

Hello there.

I had an overboost problem when the engine was cold (sticking turbo veins) I used some archoil in my fuel tank, caned it and since this and driving a lot better, the fuel economy has halfed.

I was originally getting 120 miles to 16 litres. Now I'm only getting 60.

It's an automatic which had a gearbox oil change last summer. The mileage is 170,000.

I changed the thermostat last week as the temperature struggled to reach 80 degrees. Now it sits happily at 3 bars above 80.

Had it scanned.

Map sensor high reading and overboost codes only

Nothing to do with fuelling.

Any ideas?

 

[mersum1es]

Might be still turbo problem... If vane has been jamming also actuator may be damaged. I assume air filter has been changed, no boost leaks etc...

 

[RUBBER_UNDIES]

Might be still turbo problem... If vane has been jamming also actuator may be damaged. I assume air filter has been changed, no boost leaks etc...

Thanks for the reply.

The car is driving perfectly. Best it ever has. There are no leaks. It had two new intercooler pipes this year.

The intercooler is fine. If the actuator was damaged would it drive poorly?

The fuel gauge fluctuates I've noticed. I could drive it with 4 bars left for ten miles then the next time I start it it will be down to two. It's a lottery as to wait it will read when I next start it.

 

[Westheath]

Hello there.

I had an overboost problem when the engine was cold (sticking turbo veins) I used some archoil in my fuel tank, caned it and since this and driving a lot better, the fuel economy has halfed.

MB Star session is required.

I suspect you have boost problems.

 

[RUBBER_UNDIES]

MB Star session is required.

I suspect you have boost problems.

I have star at work. It's just when I can get onto it. What values should I be looking for?

 

[Westheath]

There's a Charge Pressure system test under CDi3 section. (E270 2003)

It runs the boost system automatically and reports on any faults.
iirc
Been a while since I used Star as Launch is 100 x faster for low impact daily use.

 

[RUBBER_UNDIES]

There's a Charge Pressure system test under CDi3 section. (E270 2003)

It runs the boost system automatically and reports on any faults.
iirc
Been a while since I used Star as Launch is 100 x faster for low impact daily use.

Thank you very much for this useful information. I'll th and do it tomorrow.

 

[thebiglad]

What is "Launch" please and where can I get further information - I'm searching for a competent diagnostic kit that I can afford, to use on my W209.

 

[Wighty]

What is "Launch" please and where can I get further information - I'm searching for a competent diagnostic kit that I can afford, to use on my W209.

No idea on launch but have you considered the icarsoft i980 and MB2 ?

 

[abazem]

Thanks for the reply.

The car is driving perfectly. Best it ever has. There are no leaks. It had two new intercooler pipes this year.

The intercooler is fine. If the actuator was damaged would it drive poorly?

The fuel gauge fluctuates I've noticed. I could drive it with 4 bars left for ten miles then the next time I start it it will be down to two. It's a lottery as to wait it will read when I next start it.

I have the same model as yours and it was running perfectly until I accidentally poured petrol in tank and ran it for 10 kms. The car survived after that but fuel economy has gone down. I have noticed it gets worst when it is idle. The fuel guage also moves up and down. Fuel economy is 10 litres/100 km if that helps you at all.

 

[Westheath]

What is "Launch" please and where can I get further information - I'm searching for a competent diagnostic kit that I can afford, to use on my W209.

These are not dedicated to Mercedes vehicles.

http://www.launchtech.co.uk/oem-level-diagnostics/launch-x431-pro

Also for non pro stuff much cheaper but very powerful.

http://www.launchtech.co.uk/enthusiast-diagnostics/

 

[RUBBER_UNDIES]

These are not dedicated to Mercedes vehicles.

http://www.launchtech.co.uk/oem-level-diagnostics/launch-x431-pro

Also for non pro stuff much cheaper but very powerful.

http://www.launchtech.co.uk/enthusiast-diagnostics/

Thanks for the info.

I've had some live data off the car. The map sensor at full boost is reading 34 psi at wide open throttle. Does this sound okay to you?

I've been using DELPHI. It's not star but very comprehensive. Can do sbc work etc and gear box. The whole car basically. Scans everything.

 

[RUBBER_UNDIES]

I have the same model as yours and it was running perfectly until I accidentally poured petrol in tank and ran it for 10 kms. The car survived after that but fuel economy has gone down. I have noticed it gets worst when it is idle. The fuel guage also moves up and down. Fuel economy is 10 litres/100 km if that helps you at all.

Thank you very much. Please tell me you found the solution abazem?!

 

[RUBBER_UNDIES]

Delphi brilliant. I use that. Does everything. You need a laptop though.

What is "Launch" please and where can I get further information - I'm searching for a competent diagnostic kit that I can afford, to use on my W209.

 

[RUBBER_UNDIES]

Sounfs like you may have damaged your high pressure fuel pump or injectors.

I have the same model as yours and it was running perfectly until I accidentally poured petrol in tank and ran it for 10 kms. The car survived after that but fuel economy has gone down. I have noticed it gets worst when it is idle. The fuel guage also moves up and down. Fuel economy is 10 litres/100 km if that helps you at all.

 

[oigle]

Thanks for the info.

I've had some live data off the car. The map sensor at full boost is reading 34 psi at wide open throttle. Does this sound okay to you?

I've been using DELPHI. It's not star but very comprehensive. Can do sbc work etc and gear box. The whole car basically. Scans everything.

34PSI......whew. That is waay too high. I would suggest about 15psi is normal. 34 will blow hoses and maybe even intercooler.

 

[RUBBER_UNDIES]

34PSI......whew. That is waay too high. I would suggest about 15psi is normal. 34 will blow hoses and maybe even intercooler.

Would it be turbo then perhaps?

 

[LostKiwi]

Would it be turbo then perhaps?

Boost control. Bad turbos don't overboost, they fail to boost.

 

[RUBBER_UNDIES]

Boost control. Bad turbos don't overboost, they fail to boost.

Don't be so cryptic!

Could it be the actuator?

Fuel consumption is really bad......

 

[LostKiwi]

Don't be so cryptic!

Could it be the actuator?

Fuel consumption is really bad......

Yes actuator. That's what controls the boost.