w202 stalling, losing power - auto

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KillerHERTZ

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Last night, I was driving along in my w202 when it tried to go into 2nd (I think, its an auto) and it started losing power and I had to pull over, it then stalled - somthing I thought was impossible on an auto!

Ive had the car 3 months and its never happend, I asked my brother who owned it before and he said it happend on hot days about once a month.

I went to my garage and they couldnt find any fault and recommended I go to MB to have a system check done on it.

Does anyone have any idea what this maybe?

It was serviced/Mot'd last week with no trouble at all.
 
If I had to guess...

Air Mass Flow Sensor (a.k.a. MAS) has failed. This can cause all sorts of strange symptoms.

I had mine fail recently as did GrahamC230K and the jury is out on whether Robbo has the same problem.

Take it to the dealer where they can hook it up to the Star Diagnostic computer.

If it is the MAS don't expect much change from £300, the labour is cheap but the part is exbenzive. Check out the threads 'ECU Glitched' and 'MAS strip down'.

S.
 
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My fren, C180 is not fitted with MAS.

It happended on my before, story quite similar to yours, my brother sold it to me and saying that it was "perfect". But since then I spend US$1,500 on repair and replacement of parts :( Almost all the parts (which need replacement in 5-7 years) were replaced by me. sigh.....

Well, back to your question, I dunno what it calls, it has got something to do with fuel injection unit. Thought our model not fitted with MAS, it does have something right before the fuel injection unit to control the air (or something like that). Also pls get the mechanic to check the electronics code (those deal with the air flow, fuel supply etc).

Hope this helps.
 
Originally posted by BBW
Last night, I was driving along in my w202 when it tried to go into 2nd (I think, its an auto) and it started losing power and I had to pull over, it then stalled


I was about to say same thing as Steve Perry as that is EXACTLEY waht happened to me.

If you don't have a MAS (Mass Air Sensor) then you must have an Air Flow Meter, or something......no mechanic but these fuel injected cars have something to control this.

I had an Air Flow Meter go on my BMW - even more expensive than the MAS on my MB, but again, ran much sweeter afterwards.


I wait in anticipation to find out what it is...................
 
has any one managed to source a supply of these MAS units direct from if BOSCH say a BOSCH agent etc. Are these a DIY install or when the MAS is replaced do codes need to be reset to make the engine run smoothly again.
 
Originally posted by Andy W
has any one managed to source a supply of these MAS units direct from if BOSCH say a BOSCH agent etc. Are these a DIY install or when the MAS is replaced do codes need to be reset to make the engine run smoothly again.

To answer this as a side note (as we have already established a C180 won't have a MAS).

Jimmy tried to get me a MAS through a Bosch agent he knows with no luck at all. Part is not recognised.

Part is DIY install (even for me) and does not need to be programmed to work, but you do need a dealer to clear the fault codes, otherwise they will be left on history as it were.

Aparrently my ECU did not have any record of a problem, until the new MAS was plugged in, then it figured it did have a problem before hand!! wierd.
 
I was not aware that the C180 does not have a MAS, does it just have an air flow meter ?
 
Cheers for your replies guys.

I forgot to mention, just before it stalls, the engine sounds like its stuttering and coughing etc...

When I put it into Standard rather than Economy, it seemed to help it.

Its happened 3 times in 2 days, and before this I hasnt done it for months.

When it had its service, could someone have disturbed this MAS thing?
 
Originally posted by BBW

I forgot to mention, just before it stalls, the engine sounds like its stuttering and coughing etc...

Still sounds familiar!


Originally posted by BBW
When it had its service, could someone have disturbed this MAS thing?


I understand this is common for a MAS! My dealer said they often have customers comming back with MAS failure shortly after service!!! Apparently a service bulletin was issued to all stealers warning to be carefull when replacing air filter etc.

However, I believe an Air Flow Meter has adjustment, so maybe this was altered or needs altering since the service.
 
Yes!, It had a new air filter fitted!!!

My garage is a recognised MB garage, but doesnt have the Computer link up things.

Do MB charge for the tests then?
 
It normally costs, but depends how friendly they are. Never heard of a dealership without a Mercedes diagnostic machine!
 
My local dealer wanted £35 just for a Star Diagnosis hook-up and print-out when I asked them last year.

I dunno what their response would be now, now that we've developed a bit of a rapport (i.e. me spending $hitloads of money for their benefit :p )

Just out of interest GF was telling me a few weeks back that he now has an official Star Diagnostics computer. Have you seen this yet K.?

**EDIT** BBW, however your air is metered into the engine, to me it sounds like this sensor/meter is playing up but the only way to be 100% sure would be an ECU fault print out.

S.
 
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Originally posted by GrahamC230K
It normally costs, but depends how friendly they are. Never heard of a dealership without a Mercedes diagnostic machine!

Its not a dealership, only a garage which is endorsed by MB,

Cheers people, I will look into it
 
Originally posted by GrahamC230K
To answer this as a side note (as we have already established a C180 won't have a MAS).


Not one to be awkward my dads S reg C180 does have a MAS
 
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Originally posted by pluggers
Not one to be awkward my dads S reg C180 does have a MAS

Only going on what people said - not preaching with any actual knowledge!!

OK, so I reckon we are safe to say early C180/C200's dont.

Am I remembering correctly, that your C200 doesn't have one pluggers?
 
No mine hasn't either as you say the early one dont have them.I am not sure on this but I think they became common place on the face lift models with all the updated fuel injection and engine management systems.
 
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all face lifts had MAS.

A friends car has the symtoms and it's not his MAS it's his ECU....

£1200 for a new one on order!
 
Originally posted by Koolvin
all face lifts had MAS.

A friends car has the symtoms and it's not his MAS it's his ECU....

£1200 for a new one on order!

A guy at work had his ECU fail on his R reg Ford Fiesta a year or so ago... £700 for a replacement.
:crazy: d@mn these things are exbenzive, no matter what the make of the vehicle.

S.
 

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