Bad Fuel Consumption

[design guru]

I have a 2001(51) CLK 230K. It drinks quite a lot of fuel per week compared to usual. Can anyone pinpoint the main parts that cause this?(ie. filters, plugs ect..)

I used to get to and from work n £10 a week, now its touching £25.(nothing to do with the fuel increase, I've taken that into account)

 

[BTB 500]

Could be a faulty airflow sensor (MAS), causing the wrong mixture to be set.

 

[Parrot of Doom]

Might also the lambda sensor on the exhaust.

 

[Dieselman]

The colder weather won't be helping as the engine runs rich for much longer.

 

[Ian B Walker]

Or heavier shoes

Ok so I am being sent to the naughty corner

 

[merc man]

can be either or both lambda or maf, best to get it on a sart and read the live data, i suggest Blackc55 for this, he knows his stuff!

 

[television]

The colder weather won't be helping as the engine runs rich for much longer.

And dont I know that, the average 13.8mpg on mine after the first 5 miles.

 

[esox]

And dont I know that, the average 13.8mpg on mine after the first 5 miles.

Yeah,but after it warms up the heavier,denser,cooler air is good for combustion.
Make your journeys longer then five miles......

 

[Dieselman]

And dont I know that, the average 13.8mpg on mine after the first 5 miles.

A petrol uses 4 times more fuel over the first 2km than a diesel. Bet you wanted to know that.

 

[television]

A petrol uses 4 times more fuel over the first 2km than a diesel. Bet you wanted to know that.

Can you please delete the post, I do not want to know that.

I would be happy with a diesel SL, why not

 

[robert.saunders]

Oh that's just wrong - imagine a diesel Bentley

 

[television]

Oh that's just wrong - imagine a diesel Bentley

This is only the way that we have been brought up, and our way of thinking

http://www.leftlanenews.com/bentley-considers-diesels-hybrids.html

 

[robert.saunders]

This is only the way that we have been brought up, and our way of thinking

http://www.leftlanenews.com/bentley-considers-diesels-hybrids.html

Pah, that's VW meddling

 

[Glenn Smith]

I have a 2001(51) CLK 230K. It drinks quite a lot of fuel per week compared to usual. Can anyone pinpoint the main parts that cause this?(ie. filters, plugs ect..)

I used to get to and from work n £10 a week, now its touching £25.(nothing to do with the fuel increase, I've taken that into account)

How many miles are you doing? what kind of driving? is the the "old" type 230k engine like mine? if so £10 will get you about 45-50 miles maybe 60-70 on a long run (steadyish driving).

I was looking at the instant fuel consumption computer on the jag the other day whilst in stop start traffic and it was in single figures!

 

[BlackC55]

Get the air mass and Lambda values checked. Make sure the service items are in good condition and use a premuim fuel.

 

[dsolds]

Get the air mass and Lambda values checked. Make sure the service items are in good condition and use a premuim fuel.

Do these premuim fuels (with their premium prices) actually cost you less per mile than regular unleaded? I have always (without foundation I admit) avoided them as they are usually about 20p a gallon more expensive in the first place.
If we take the cost difference as being approximately 4 or 5 % then my E500 should see an increase of 1 to 1.5 MPG since I get 20 urban and 30 on a run.
Would this really be the case?
Dom

 

[BTB 500]

Premium fuels have been discussed here several times ... run a few searches and you should find the threads.

Basically the more highly-tuned the engine the more benefit you get. My V6 VW Sharan did get better mpg (based on long cross-Europe trips in cruise control, so fairly controlled conditions) on Shell Optimax / V Power. And there was an increase in torque, noticeable when towing.

Read this, Optimax (98 RON) has been replaced by V Power (99 RON) now:

http://fifthgear.five.tv/jsp/5gmain.jsp?lnk=601&featureid=143

 

[television]

BTB 500 has answered. You can tune to a point where you must use the 98 though most MBs will rune on 95 all of the details are in your handbook under fuel