A Class - is it, or isn't it....?

[BabyBenzBoy]

I have been advised that I need to change the the throttle body on my partners A140, to get the part I need to provide the existing part number. Looking on the car the number I've located is A1661500179(2) - when searching for this, the part that comes up is the Air flow and ECU unit - is this also the throttle body?

If not what would the throttle body number look like - and where is it located in relation to the AF/ECU unit?

The fault codes that led to this diagnosis from the garage were (this is how he wrote them down):

P0170 - Self adaption idle too rich
P0170 - SH Time Self part load excess
P0170 - Low part load too rich
P0100 - Hot film MAF sensor malfunction

Also if it is the AF/ECU unit, I understand that these need to be coded to the car - who can do this?

Cheers

 

[Ultymate]

I'd be looking at the MAF sensor first as that is likely if faulty to throw up the other faults in your list, you could even try running the car with the MAF disconnected as the ECU will then substitute an average data figure for it, and see if it runs better with it disconnected

 

[bundy]

hi, the throttle body on your a class is part of the ecm (engine control monolith) as is your maf sensor. the unit can be repaired by bba reman assuming its the maf thats faulty, & looking at your adaption codes this is likley the case.

good luck
regards ted

 

[BabyBenzBoy]

The garage that is doing the work (not my choice, this is led by by the dealer who I got the car from) has said that as long as the part number for this is the same as the swapped part there is no need to have the unit 'coded'. From what I have read on this forum and other sources, if the existing unit is re-conditioned then it is ok, but any swapped out units have to be coded to the car.

What is the correct answer here - why does the unit have to be coded, what happens if it is not done?

Cheers

 

[BabyBenzBoy]

Anybody? - Can you swap out a second hand ECM unit without the need for re-coding?

Cheers

 

[bundy]

nope you cant swap it for a secondhand one, it must be coded to match your ecu. sorry

regards ted (mercedes centre liverpool)