Car had been left for 3 hours outside at 2C, so 2nd start of the day.

 

Initial rpm was 650.

 

I reverse from cul-de-sac.

 

I stop, put car in D, drive only for 2 metres, then bring car to stop because of traffic. 

 

Car seemed slow to stop. Like it was surging. And once stopped, juddgered violently at 650rpm. 

 

I didn't put it into neutral because I needed to move off, I was looking at cars. The juddering disappeared as I moved off after a few more seconds. 

 

However, once I left the estate, and I came to a stop at the first traffic light in D. The revs were now holding at 1k. 

 

So my working hypothesis is that the low revs when cold has caused the juddering. 

 

It only happened in D when 650rpm. Not when in P/N when car was started. 

 

There seems to be a pattern (from yesterday) when I also left the car for 3 hours, then started again. 650rpm initial idle rev. Upping to 1k after having driven half a mile out. 

 

In the morning when car is left out overnight, rev at idle is immediately 1k. 

 

---

1) why is there juddering when in D at low revs but not in N at cold weather? 

 

Why did it seem to surge? 

 

2) why didn't the car start for the 2nd time of the day at 1k immediately? It started both yesterday and today at 650, and only then seeming to realise it's colder then it thought. Why was it the ECU fooled and how did it correct itself after half a mile? 

 

3) did the juddering episode today damage anything? 

 

(no lights or codes with Carista reader) 

 

---

Sorry if I read like I'm paranoid, which I kind of am. I really need the car to not break down this winter, its final winter really. Going to extreme lengths to protect the health of the car. 

6 hours ago, newskodadriver said:

Car had been left for 3 hours outside at 2C, so 2nd start of the day.

 

Initial rpm was 650.

 

I reverse from cul-de-sac.

 

I stop, put car in D, drive only for 2 metres, then bring car to stop because of traffic. 

 

Car seemed slow to stop. Like it was surging. And once stopped, juddgered violently at 650rpm. 

 

I didn't put it into neutral because I needed to move off, I was looking at cars. The juddering disappeared as I moved off after a few more seconds. 

 

However, once I left the estate, and I came to a stop at the first traffic light in D. The revs were now holding at 1k. 

The engine is just and only just warm enough to stop the cold start pre-heat engaging fully.

@newskodadriver

Important info.

What engine the car has, and what DSG. 

Is it a DQ250 6 speed wet clutch DSG that requires servicing,  or a 7 speed DQ200 that does not?

 

How many miles has the car done? 

 

PS

the 650 rpm is very low, possibly causing the issue. 

 

Edited 20 November, 20241 yr by Ootohere

13 hours ago, Ootohere said:

@newskodadriver

Important info.

What engine the car has, and what DSG. 

Is it a DQ250 6 speed wet clutch DSG that requires servicing,  or a 7 speed DQ200 that does not?

 

How many miles has the car done? 

 

PS

the 650 rpm is very low, possibly causing the issue. 

 

DQ250 6 speed wet

 

Also, it would have been 750 rpm. I misread the analogue needle, sorry. I looked more closely today at the normal resting rate. The higher rpm at idle would have been 950

On 20/11/2024 at 04:15, Paws4Thot said:

The engine is just and only just warm enough to stop the cold start pre-heat engaging fully.

BTW that issue was solved where if I thought the engine shouldn't be warm enough to start at 750rpm, I simply press the accelerator manually in Neutral to raise the rpm to 1k and hold it there for 30 seconds to 1 min. 

 

After that, if the engine was as cold as I thought, it would hold itself at 950rpm thereafter until it was properly warmed up. 

 

I think there is a mismatch in sensor readings somewhere and revving the engines manually for a little while gives the system time to reach the correct conclusion

Edited 24 November, 20241 yr by newskodadriver