Audi 1.2TDI Rückwärtsgangproblem

[Miguel Silva]

Sehr geehrte Damen und Herren,
Ich spreche kein Deutsch, also verwende ich Google, um von Englisch nach Deutsch zu übersetzen. Es ist mein erster Beitrag hier (ich habe in der Vergangenheit in A2OC gepostet).
Ich habe mir 2011 einen Audi A2 1.2TDI gekauft und der Rückwärtsgang hat fast von Anfang an ein Problem. Wenn ich den Wählhebel in die Position R schiebe, rastet der Rückwärtsgang nicht ein und die Schalttafel zeigt die Position N an. Ich fand heraus, dass der Wählhebel immer noch in Position R ist, wenn ich den Wählhebel nach oben ziehe, indem ich die 'Hülse' halte und gleichzeitig die 'Abdeckung' niederdrücke (nur mit einer Hand). Der hintere Gang rastet mühelos ein. Ich habe das Auto einmal zu Audi gebracht, sie haben einige Teile im Bereich der Wählmechanik ausgetauscht und das Problem war für einige Wochen weg, aber es kam zurück. Es scheint, dass eine Grundeinstellung das Problem auch für einige Tage / Wochen löst. Die Kupplungsscheibe, die Führungshülse und das Kupplungslager wurden kürzlich ersetzt. Der Druckspeicher ist fast neu. Alle anderen Gänge funktionieren einwandfrei.
Hat jemand ein ähnliches Problem und / oder kann mir helfen? Vielen Dank.
Freundliche Grüße,
Miguel

 

English:

Dear all,
I don't speak german so I'm using google to translate from english to german. It's my first post here (I have posted in the past in A2OC).
I bought in 2011 an Audi A2 1.2TDI and almost since the beginning the reverse gear has a problem. Sometimes when I move the selector lever to R position the reverse gear does not engage and the dash panel indicates N position. I found out that, with the selector still in R position, if I pull up the selector lever by holding the 'sleeve' while pressing down the 'cover' at the same time (using only one hand), the rear gear engages effortlessly. I took the car once to Audi, they changed some parts in the selector mechanism area and the problem was gone for a few weeks but came back. It seems that doing a 'basic settings' solves the problem for some days/weeks also. The clutch plate, guide sleeve and clutch bearing have recently been replaced. The pressure accumulator is almost new. All other gears work perfectly.
Has anyone had a similar problem and/or can help me? Thank you.
Best regards,
Miguel

Bearbeitet 23. April 2019 von Miguel Silva

[DerWeißeA2]

Even if I don't understand what you are doing with the selector lever , I'am pretty sure your issue is a faulty clutch slave cylinder.

[Miguel Silva]

Thank you for the reply DerWeisseA2 (I wished mine was white also, marine blue is hotter in the sun/summer).

The clutch slave cylinder is brand new and using VCDS to check its values, I don't see any problem.

In fact, after searching harder in the forum, similar problems has been mentioned here:

The user Kolja, describes moving the gear selector to tiptronic lane and then back to R to solve (temporarily) the problem. If I do the same it also helps in my case.

Someone else (I don't find the thread now, sorry) mentions pushing the selector sideways when in R position and this also makes it work in my case. This is my solution now for the moment (it always works).

I suspect there's some 'play' in the gear selector mechanism and this is changing the value in the potentiometer G272. I clearly see it using VCDS by pushing sideways the selector to force the problem to show up: it indicates it's in N or R (attached photos).

The problem happens with either motor running or not (so I don't think it's related to the transmission shaft not being stopped). Rear lights are good also. I have no problems (RTFM, etc) doing the Basic Settings.

I'm hoping someone could confirm this possibility (i.e. play in the selector lever mechanism) and what could I do to fix it. An official Audi garage tried to fix the problem but it came back after some time(I don't think they fixed anything after all, they were "lucky").

Thank you in advance.

[Phoenix A2]

It probably has something to do with the G272 potentiometer.

You can find the nominal voltage values of G272 for each lever position here: Wiki - Messungen und Prüfungen am automatisierten Schaltgetriebe durchführen

Try all different positions and check the voltages against the nominal values.

 

Either the G272 itself has some play/fault internally or the mechanic that connects the lever to the G272 has some play.

I would try to disassemble the covers around/below the lever and check if there is noticable play.

If not another option would be to replace the G272. Part number is: 085 907 385

A basic setting could be necessary after replacement of G272 (i would recommend it).

 

[Miguel Silva]

Thank you Phoenix A2, I will see what I can do.

 

Best regards,

Miguel