Kickdown - loss of power - C240 Auto

[Jon Browne]

When I kickdown or drive the car in sports tiptronic mode, there is next to no power. Feels like something is holding the car back. (its not the speed limiter). The car drives perfectly normally otherwise, its just when you need a bit of extra performance, its not there. Does anyone know what it could be?

 

[television]

Hello and welcome Jon,, for me I would say the MAF and you could unplug it to test...

See what others think

 

[jibcl500]

I agree with Malcolm, air flow meter, have you jump started the car recently?, replaced the battery or charged the battery?
Has the car had anywork done on it in the last week or so?

jib

 

[Jon Browne]

Thanks for the welcome Malcolm. I haven't done any of that. Where abouts is the MAF. Is this the same as the airflow mass regulator? I just found an earlier thread.

Jon

 

[Cole@MBS]

On the air intake tube after the air cleaner! 5 pin muti-plug!

 

[television]

Yes it is and its 119 in the link at the end of the air intake box

http://www.detali.ru/cat/oem_mb2.as...623716.634&CT=M&cat=19X&SID=14&SGR=030&SGN=01

 

[Jon Browne]

Thanks for that Malcolm and S - A - M. I'll check it out. How do you test it though?

 

[television]

Thanks for that Malcolm and S - A - M. I'll check it out. How do you test it though?

Sometimes you can just unplug it and if the car goes better, though it may be a bit rough thats the answer.

£145 from a Bosch service center or £250 from MB

 

[Jon Browne]

Thanks again Malcolm. I've just looked on ebay and they are on at @£40.

Jon

 

[television]

Thanks again Malcolm. I've just looked on ebay and they are on at @£40.

Jon

If it is not a Bosch,, the chances are that it will fail in a few weeks, and that has been the case with the ones on here

You can look here but no one here has used them yet

http://www.airmassmeters.com/

 

[Jon Browne]

Thanks for the link to the description of the air intake box malcolm but I don't think this is my engine. You just lift off the top cover with "Mercedes Benz" on it together with the intake pipes. There are no wires attached to it and there are two air filters, one each side. I cant find anything that looks like the MAF sensor. My car is the 6 cylinder 2.6 version. Can you help.

Jon

 

[Cole@MBS]

Ah, you have the later of the two then, where the large airbox meets the airmass at the back of the engine, that is the sensor we are talking about, again, have a 5 pin muti-plug on the side!

 

[Jon Browne]

Yes, I know where you mean. If I disconnect that, and run the car, should it react the same. ie more power but slightly rougher if it is this sensor.

 

[television]

Yes,, if the car has more power, though idle may be rough it will give an indication, you cant do any harm and do it on a warm engine

 

[Jon Browne]

Thanks for that Malcolm. It seems that was the problem. I disconnected the sensor when the engine was warm and now it is a different car altogether. Felt almost like it was supercharged compared with before. Thanks for all your help.
Regards
Jon