Can Oil Overfill damage MAS Sensor

[mobeyone]

And misfiring from idele up to 2500 revs - but not smoking or anything else.

Hope this helps you.

thanks for the reply - really need to read up a bit more on this.

But my problem is that anytype of misfire must have a fault code stored somewhere in the car?

 

[tamrsoft]

It's a simple job to remove the MAF Sensor on an E220 CDi, one connector and two self tapping torx screws. If its covered in oil and deposits, clean it off with an electronic components aerosole spray (do not not use Carb cleaner or WD40), you can buy it from halfords. Replace and see if it helps, its a cheap first pass check.You should not normally get any oil on it since the oil breather goes into the Charge Air pipe down stream of the turbo.

 

[stats007]

I was under the impression that once contaminated by oil, cleaning the wire has no effect as it is burnt on.

 

[tamrsoft]

The unit fitted on my engine appears to have a film sensor and not a wire sensor. Even with a wire sensor, iso-propyl alcohol spray should clean it off if not too badly burned on.

Apologies to all for the earlier double entry

 

[aka$h]

I was under the impression that once contaminated by oil, cleaning the wire has no effect as it is burnt on.

I did this on my CDI and cleangin it worked, the turbo gasket was leaking and the engine bay had a fair amount of soot in it, as a result cleaning the MAS worked. So its worth a try, you've got nothing to lose.

 

[andreas_t]

thanks for the reply - really need to read up a bit more on this.

But my problem is that anytype of misfire must have a fault code stored somewhere in the car?

Apparently, it only stores codes relating to the electronics in as far as the engine management is concerned. So, if you have a mechanical fault - like mine was - it does not register any fault codes.

If the MAF has a problem, it will show in the fault codes. Steve 'simulated' a fault with the MAF on mine and, sure enough, it came up in the fault codes.

What mileage have you done ? - I have 85k on the clock.

Hope this helps.

 

[andreas_t]

As an afterthought, a problem with the MAF sensor should not cause a misfire..... just a loss of power.

The MAF's operation is based on hot wire anemometry - so it could either be a wire mesh (measuring temperature drop as air passes through) or a film (same idea, but this time it uses a boundary layer technique to measure airspeed and, hence, mass).

The end effect is that you are running 'rich' or 'lean' - depending on a number of conditions.

I am sure that someone more technical will put me right if I've goofed.