A2 1, 2 TDI keine Bewegung nach langem Leerlauf im Stau? Warum?

Hi my german is not so good so I have written in English and than Google translated. Can see a lot of errors in the tarnslation but hopefully possible to understand !

First English variant

When in a traffic jam so the car will idle for a long time, after that the car doesn’t move. I have to disconnect the battery and after that the car works again. If I stop the engine in this state the car doesn’t start before I have disconnected the battery.

I haven’t been able to read out any failure code as this happens in traffic and after disconnection of the battery the code will be erased.

The car works normally if I am not coming in this “long idling”.

The only thing that is not normal is that the car starts, before I believe the hydraulic pressure has built up. This means that engine runs but no gears will engage directly. If I wait to start the engine until the hydraulic pumps stop that gears will engage directly.

I have made basic setting recently and checked hydraulic oil level.

Any idea what is the reason?

Can it be something with hydraulic pressure measurement?

Deutsch-Variante

Wenn in einem Verkehrsstau, so wird das Auto für längere Zeit im Leerlauf laufen, nach, dass das Auto bewegt sich nicht. Ich habe, um die Batterie zu trennen und nach, dass das Auto funktioniert wieder. Wenn ich den Motor in diesem Zustand das Auto nicht starten, bevor ich die Batterie abgeklemmt.

Ich habe nicht in der Lage zu lesen jegliche Fehlercode, wie dies geschieht im Verkehr und nach Abtrennung der Batterie wird der Code gelöscht werden.

Das Auto funktioniert in der Regel, wenn ich nicht in dieser "langen Leerlauf" kommen.

Das einzige, was nicht normal ist, dass das Auto beginnt, bevor ich glaube, dass der Hydraulikdruck aufgebaut hat. Dies bedeutet, dass der Motor läuft, aber keine Zahnräder direkt zu engagieren. Wenn ich warten, um den Motor zu starten, bis die Hydraulikpumpen zu stoppen, dass Zahnräder direkt zu engagieren.

Ich habe vor kurzem die Grundeinstellung überprüft und Hydraulikölstand.

Keine Ahnung, was ist der Grund?

Kann es etwas mit Hydraulikdruck-Messung sein?

/Kurt Myhr

What do you mean with "the car idle for a long time"? Do you switch the gear box manually to the neutral position?

Artur

Normally in a traffic jam I just hit the footbrake and leave the gear lever in D position. Then I know it happens that the car will not move after a long time in that situation. (long time some minutes).My son says it has happen even when he put the gear I N position, but that I haven’t experienced.

Normally in a traffic jam I just hit the footbrake and leave the gear lever in D position. Then I know it happens that the car will not move after a long time in that situation.

That is what I don't understand. In D position, the 1.2 TDI engine stops normally after two seconds while holding the foot brake. Providing you didn't turn off the ECO Mode before. It shouldn't idle.

OK, what happens next? You press the throttle, the engine speeds up, but the car won't move. Is that right?

How many seconds does the hydraulic pump run before you start the engine? How many gear lever changes are you able to perform before the pump starts again? When was the last time you replaced the oil pressure accumulator?

The engine stop very seldom because of the start/stop function even in eco mode as in Sweden you always have the light on (day running light) and others loads. (One condition for engine stop at start/stop is load factor alternator below 55 %).

So engine runs, when hitting the accelerator the engine don’t react it continues idling and car doesn’t move.

Haven’t tested number of times I can change gear before the hydraulic pump start lately and never changed pressure accumulator. Will do change pressure accumulator and see what that brings.

Clean or renew the brake pedal switch. Maybe that solves your problem.

Mark

Clean or renew the brake pedal switch. Maybe that solves your problem.

Just wanna write this. Damn, too late!

Maybe you want to try the new green stop light switch 1C0 945 511 A. Works fine and looks solid as a rock.

@Mark: Kennst du dieses Phänomen dass der 1.2er manchmal nicht auf das Gas reagiert?

when hitting the accelerator the engine don’t react it continues idling and car doesn’t move.

Check also the accelerator pedal module. It contains the accelerator position sender G79, the idling speed switch F60 and the kick-down switch F8.

Sorry for one posting after another, but there might be an another issue I had lately myself. Discard the accelerator pedal module.

If the clutch slave cylinder doesn't react (or doesn't tell) within one second after the signal from the gear control unit (GCU), the GCU tells the motor control unit to switch in an emergency mode. That's why the engine doesn't react.

The reason, among other things, may be: an wide-stretched hydraulic pressure accumulator, a worn out potentiometer at the clutch slave cylinder or the clutch cylinder itself.

Are you confirm with the basic adjustment of the electronic gear unit? When was the last time it was done?

Normally in a traffic jam I just hit the footbrake and leave the gear lever in D position.

Really sounds like the clutch slave cylinder.

But make sure you never use the handbrake in that situation instead of the footbrake.

Thank you all for all good advises , will come back when I started to locate the error(s).

MFG Kurt Myhr

 

@Mark: Kennst du dieses Phänomen dass der 1.2er manchmal nicht auf das Gas reagiert?

Ja, kenne ich auch. Trat bei meinem mal sporadisch auf. Im Fehlerspeicher war nichts hinterlegt. Woran es liegt – keine Ahnung.

Problem solved.

Thanks for all good advice!!

Problem was the pressure accumulator. I have never changed the unit as I mentioned earlier. The car has now made approx. 280Kkm and I bought it when it made aprox. 11Kkm

MFG Kurt Myhr

Thanks for the Feedback!

I was not aware that a defective pressure accumulator could have such severe effects.

I am anyways a fan of changing the accumulator regularly every 2 years since I noticed a decrease in driving comfort an an increase in the time that one must wait for starting. I don't know how much it costs in your place, but here it's about 40,- and it's worth it!