newbie to this site and my ML270 please help

[mark sutton]

First of all hi to everyone

Please be gentle with me as I am a newbie to this site and to my mercedes ML270 only had it 3 weeks and I am trying to sort out all the little problems like water in drivers foot well found pipe from gutter of sunroof had popped out of it's holeand water was going all over the fuse box, pulled elbow off pipe cleared debris from pipe refitted elbow and put back in it's hole, problem solved then I started to loose power and would not rev above 2200 and changed gear really quickly could not find out why so I found this site and I have printed off some of the threads which I am going to try first.

I have always done my own servicing with the help of my hanyes manual but hanyes don't do one for the ML270 is there any manuals I can buy that show me where things are and could anyone tell me what EGR & MAF mean.

Many thanks

Mark

P.S I will try to contribute as much as i can to this site with detailed pictures and text

 

[television]

Hi Mark and welcome.

The EGR valve is a device in the exhaust manifold that returns harmful gasses back to the air intake while cruising on light throttle. with age / high miles they may stick open and cause poor running

The MAF is the most common fault, it is a sensor that measures the air temp and air flow into the engine and sets the main ECU up for the correct mixture,

You can often just unplug it to test to see if the engine is better without it

 

[JEZ.S320L]

First of all hi to everyone

Please be gentle with me as I am a newbie to this site and to my mercedes ML270 only had it 3 weeks and I am trying to sort out all the little problems like water in drivers foot well found pipe from gutter of sunroof had popped out of it's holeand water was going all over the fuse box, pulled elbow off pipe cleared debris from pipe refitted elbow and put back in it's hole, problem solved then I started to loose power and would not rev above 2200 and changed gear really quickly could not find out why so I found this site and I have printed off some of the threads which I am going to try first.

I have always done my own servicing with the help of my hanyes manual but hanyes don't do one for the ML270 is there any manuals I can buy that show me where things are and could anyone tell me what EGR & MAF mean.

Many thanks

Mark

P.S I will try to contribute as much as i can to this site with detailed pictures and text

Hello and welcome to The Forum.

MAF = Mass Airflow something or other, and is vital to the well-being of the engine. Don't be tempted to buy a cheap one off eBay (they are fake - cheap, but useless). They are made by Bosch and can be purchased cheaper direct from Bosch, than from MB.

There you have it - I'm useless on the technical side - I just drive the ****** things..!!

Enjoy! They are brilliant

 

[mark sutton]

very helpfull

Hi Malcolm

Thank you for the info I will look into that tomorrow.

many thanks

 

[mark sutton]

also helpfull

Hi Jez

I am going to try cleaning it first and see what happens if there is no change I will try unpluging it if that dosn't work I will buy a new one.

I have to sort this out as I am going on a 500 mile trip on the 23rd

many thanks

Mark

 

[television]

If it is a Bosch one cheapest from Bosch.

 

[mark sutton]

MAF (Mass Air Flow) sensor on my ML270 cdi

Hi Guys

Well I did not mess around trying to clean my old MAF sensor I just bought a new one from eurocar parts for £56 including vat, I have fitted it and only time will tell if my problem has gone away.

Thank you all for your input

I have added some pictures Of the MAF sensor and it's location for other new members.

 

[A210AMG]

Hello and Welcome.


If it is the MAF and you have changed it surely its better straight away? no need for time to tell??

Hope you enjoy your car ours is great

 

[mark sutton]

intermitent

Hi
Only said time will tell as it was an intermitent fault there for a couple of days then ok for 3 or 4 on regular patern but everything ok at the moment fingers crossed.

And yes I will enjoy this car very much

mark...

 

[Mark A]

Mark. Did the new MAF sort your problem or are you still struggling ??

I have a similar problem with the wifes ML, and have tried disconnecting the MAF but it doesn't appear to run any better.

Mark A

 

[mark sutton]

MAF sensor

Hi All

well it's been a few months now since I changed the maf sensor I did about 800 miles before I got the get home safely mode back now I happens 4/5 times a week but I just pull over turn off wait 10 seconds or so restart and it OK again.

I am now going to clean my old MAF sensor with Isopropyl Alcohol and put it back on my ML to see if it makes any difference.

I will post the results in 2/3 week time.

 

[mark sutton]

MAF sensor

Hi All

well it's been a few months now since I changed the maf sensor I did about 800 miles before I got the get home safely mode back now it happens 4 to 5 times a week but I just pull over turn off wait 10 seconds or so restart and it OK again.

I am now going to clean my old MAF sensor with Isopropyl Alcohol and put it back on my ML to see if it makes any difference.

I will post the results in 2/3 week time.

If anyone has any ideas y I am still getting this trouble please let me know.

Mark.

 

[JEZ.S320L]

Mark. Did the new MAF sort your problem or are you still struggling ??

I have a similar problem with the wifes ML, and have tried disconnecting the MAF but it doesn't appear to run any better.

Mark A

Hi there. Surely by disconnecting your MAF and finding no difference, that in itself may indicate that the MAF is 'SNAFU'.

 

[mark sutton]

Hi All
Well I cleaned my old MAF sensor and if was worse, every time I drove it it went into limp mode so put new MAF sensor back in and now seems to be doing it just as much as with the old one so not sure it is the MAF sensor ?.

I have now disconnected the battery and I will reconnect it in the morning, the ECU should loose it's memory but when I restart it the ECU should start to learn again and hopefully limp mode will not reacure.

I will let you all know the results soon.

 

[hawk20]

Did you use a Bosch MAF same as original equipment. From other threads it seems cheap copies are often worse than useless.

 

[mark sutton]

pierburg MAS sensor

No I did not fit a cheap copy off ebay a genuin Pierburg £56 from eurocars

 

[Geryatrix]

When my MAF sensor went faulty, my indie replaced it but then had to use his Star terminal to reset the fault in the ECU. I don't know if just disconnecting the battery will reset the fault codes, hopefully someone with more knowlege that me will be along soon.

 

[hawk20]

No I did not fit a cheap copy off ebay a genuin Pierburg £56 from eurocars

But that is not original equipment is it?

 

[oigle]

But that is not original equipment is it?

Yes, they are the OE manufacturers of the unit for the ML270 for MB.

 

[psmart]

When my MAF sensor went faulty, my indie replaced it but then had to use his Star terminal to reset the fault in the ECU. I don't know if just disconnecting the battery will reset the fault codes, hopefully someone with more knowlege that me will be along soon.

The codes are just stored, generally they dont need resetting to rectify any engine problem, they just clear them out so that the next check reveals any new faults since the previous check. Disconnecting the battery wont clear logged faults as these are stored in 'permanent' memory in the ECU.

As per Oigle, Pierburg are the manufacturers for the MAF (at least the original part (late 2000) and the new part bought from Merc (2 months ago)) are made by pierburg.