W220 S500L Fuel consumption 40L/100LKm

[mwhtse]

I just bought a 2000 S500L and since then the Fuel consumption is showing 40L/100KM in the dash board. Well, it uses a lot -- I mean a lot of petrol.

I took the car for a check up and there is a computer error code saying the left and right side air-fuel ratio is defaulted to maximum? The shop was saying that it could be the air flow meter, or O2 sensor but cannot be sure... They need to change one at a time...

Have anyone seen it before? BTW, other than the fuel consumption, the engine seems to run smooth and fine.

Also, there is another intermittent fault code of the "link" between the transmission and the computer. The shop say sometimes they come up but if changing gear is not a problem then do not need to worry about it.

Many thanks in advance....

Regards,
Michael Tse

[mbdoc]

Air flow meter (mass air flow sensor) is a common failure.
Don't think that engine could use that much in any circumstance!

[mwhtse]

Other than high fuel consumption, what other sympotms should there be? The car seems to be perfect otherwise?

Also, there is an error code of 170 and 173 too.

Regards,
Michael Tse

[nhdoc]

Get it fixed and fast...running either too rich or too lean can and will damage the cats and that is a costly replacement.

[mwhtse]

Do I need any special tools other than the normal screwdriver? I suppose it is a 5 minutes job?

[Albysoo]

Guys,

I have the same issue. if I drive the car on low speed, (ie below 30km/hr)
I average 30+lt/100km.

if I sit and idle it for a few minutes, those numbers creep up to 40lt/100km

If I drive on the highway, those number come down slowly to 12lt/100km.

on the OBDII, I see my long term fuel trim is 20+.

Michael, if you have had any luck fixing it, let me know.

The car other wise runs well. Engine runs smooth, did not see any noticable hickup.

Albert