MAF problem W202 C200

[mevans]

Evening Guys,
thought I was having problems with my MAF as all symptoms went away when I disconnected it. So I bought a new unit, and it displays exactly the same symptoms as the old one. It is a tested working item.
What else could be the problem? Im assuming electrical connections between MAF and ECU or could the ECU itself be at fault?
When on default settings(i.e no MAF connected) it works absolutely fine, albeit rich!

Any help you can offer is much appreciated

Thanks

Mat

 

[Howard]

Hello , is your new MAF brand new or secondhand ?

Where did you buy it from ?

 

[mevans]

Hello , is your new MAF brand new or secondhand ?

Where did you buy it from ?

Brand new.
Euro car parts, genuine Bosch one.
Tested it on a mates car tonight and worked fine.

 

[momomo]

What type of symptoms? What is car the doing? Running rough, lack of power etc?

 

[mevans]

What type of symptoms? What is car the doing? Running rough, lack of power etc?

All of the above, plus hesitating when putting your foot down and stalling.
All go away with the MAF removed, but i cant keep running it without as i'm sure its there for a pretty good reason!

 

[grober]

Evening Guys,
thought I was having problems with my MAF as all symptoms went away when I disconnected it. So I bought a new unit, and it displays exactly the same symptoms as the old one. It is a tested working item.
What else could be the problem? Im assuming electrical connections between MAF and ECU or could the ECU itself be at fault?
When on default settings(i.e no MAF connected) it works absolutely fine, albeit rich!

Any help you can offer is much appreciated

Thanks

Mat

Clue is perhaps what I hi-lighted in bold. If running rich cures the problem maybe you have an inlet manifold leak somewhere post MAF of course. worth checking all those little pipes and their rubber connectors which can crack with age. Some folks have had problems with the ecu controlled valve to the fuel tank evaporative filter under the nearside wing. It leaks or sticks open. Easily checked by blocking off the pipe from the manifold

 

[alexander patie]

has the OLD maf been tested in the friends car? when changing the maf sensor, the self adaptation should always be reset, it will re-learn eventually but can take a few journeys.

 

[mevans]

Clue is perhaps what I hi-lighted in bold. If running rich cures the problem maybe you have an inlet manifold leak somewhere post MAF of course. worth checking all those little pipes and their rubber connectors which can crack with age. Some folks have had problems with the ecu controlled valve to the fuel tank evaporative filter under the nearside wing. It leaks or sticks open. Easily checked by blocking off the pipe from the manifold

Double checked everything and I hadnt done too good a job of reconnecting the MAF, so was sucking in from there

has the OLD maf been tested in the friends car? when changing the maf sensor, the self adaptation should always be reset, it will re-learn eventually but can take a few journeys.

After fixing the above fault it still ra rough, but took it for a hard drive and it seems to have sorted itself out:bannana: I will find out properly tommorow as it is taking me to Swindon and back.

Out of curiosity, what do these engines usually idle at? i am getting 1100rpm when cold and out of gear, 1000rpm when cold and in gear but then drops down to 600rpm when warm.

Thanks for the help guys
Mucho appreciated!

 

[mevans]

and the problem has reared its ugly head again. seems to be getting worse, idle is now eratic around 400rpm and it keeps stalling when changing gear with the wheels turned even slightly.
HELP!!

 

[alexander patie]

mat, guessing is all very well, but you need plugging in my friend.

 

[mevans]

mat, guessing is all very well, but you need plugging in my friend.

Problem is I am getting no fault code light, everything comes on and goes out again on the dash as it should

 

[alexander patie]

Problem is I am getting no fault code light, everything comes on and goes out again on the dash as it should

that does not tell you anything about fault codes, there will be some stored for sure.

 

[mevans]

that does not tell you anything about fault codes, there will be some stored for sure.

Thanks mate,
will get it booked in with the local indi see if he can tell me anything

 

[kjemmon]

kjemmon

hi there i have a c220 and the wiring harness on the engine was falling to bits so it could be a break down of the harness like mine.i was driving to silverstone and after time i belive that most of my wire were touching so the engine was getting a false reading and then i lost 2 values and had to replace the engine and the engine wire harness so far iv spent loads and had no warning light or anything kev HI does anyone know of a place for spare parts for a c220 1994-1999

 

[oilit]

my wifes c200 has done 175k, and I must admit I changed the lambda sensor when the fault code reader suggested it was playing up - but it made no difference - it was still a little sluggish. The cat was changed 50k miles ago, and now its REALLY sluggish on winter mornings - today it was changing gear all over the place and struggling to get above 10 mph (just like when the cat starts to eat itself!)

After about a mile all was good though I'm guessing its the MAF...

It only needs to last another month until the scrap man comes so keeping everything crossed it last until then

 

[bennesspipers]

kjemmon, you say 1994-1999, i think you'll find the engines changed, theres 94-95 & late 96 on. As for parts, try the MB dealer price,sometimes you get a pleasant surprise.

 

[bennesspipers]

oilit,when you scrap your car,have you got any MB wheel trims for sale,standard type without the chrome ring on the outside ?

 

[oilit]

oilit,when you scrap your car,have you got any MB wheel trims for sale,standard type without the chrome ring on the outside ?

Hi Bennesspipers - its going under the scrappage - but im afraid its the sport with alloys...otherwise i would have done a deal !

 

[mevans]

well, took the advice and got it plugged in. Turns out the thermostat is **** and staying open causing the car to stay on cold start and overfuelling. Going to ECP to pick up a new stat now and will let you know how I get on. On the plus side, ive now got a spare MAF for when this one goes **** up!!

thanks again for the advice guys

Mat

 

[mevans]

oilit,when you scrap your car,have you got any MB wheel trims for sale,standard type without the chrome ring on the outside ?

Ill have standard wheel trims going for price of postage when I find a decent set of alloys. Will give you a shout