Superb 3 - RPM Problem

[maradona]

Hi guys, I recently bought Skoda Superb 2016. 2.0TDI 190HP DSG. Car is very nice, but I noticed problem with RPM's.

When I start car, RPM's are arround 800. But, when car reach working temperature it goes on 950-1050 RPM (AC is OFF). I checked faults with VCDS and there is 1 fault (7158 - Please Check DTC Memory in CAN Gateway (J533) ). Also, DPF is checked and oil ash volume is on 0.16l, soot mass calculated is 15.48g, soot mass measured is 3.54g. Engine doesn't make noises.

Any help/advice would be great. Thanks 😀

[SuperbTWM]

Is start/stop fully operational?

[maradona]

4 minutes ago, SuperbTWM said:

Is start/stop fully operational?

I usually turn it off when starting car, but yes, it works fine.

[Warrior193]

Hello, welcome to the forum. It sounds as if it is attempting to do a DPF regen.

[maradona]

Just now, Warrior193 said:

Hello, welcome to the forum. It sounds as if it is attempting to do a DPF regen.

 

Thanks for the welcome.

I don't know anything about DPF, the car I had before Superb didn't have DPF. I drive minimum 150-200km weekly on highway, so I think that's enough to clean it. As I mentioned before, DPF looks fine on VCDS scan.

[SuperbTWM]

I only ever experience high idle when the car is doing a DPF regen or their is a very high demand on the AC. If the battery is a bit tired or their is an electrical gremlin causing the alternators output to be raised that could be another reason but that would also disable the start/stop function which you say still operates fine.

 

So based on that, i'm all out of ideas 😁

 

Is the battery original and of the correct type?

Edited 13 October, 2023 by SuperbTWM

[maradona]

2 minutes ago, SuperbTWM said:

I only ever experience high idle when the car is doing a DPF regen or their is a very high demand on the AC. If the battery is a bit tired or their is an electrical gremlin causing the alternators output to be raised that could be another reason but that would also disable the start/stop function which you say still operates fine.

 

So based on that, i'm all out of ideas 😁

 

Is the battery original and of the correct type?

I don't know anything about battery, I bought car two weeks ago. Also, VCDS shows that last DPF regeneration was before 150km, so I think that isn't about DPF. 

[numskull]

How many kms have you driven since you bought it? Have you had a sustained drive for more than 30 mins at working temp > 100km/h? If not try that. 

[SuperbTWM]

One thing the cold weather this week has reminded me of is that if you have the electric PTC heater fitted, this too will cause high idle if it kicks in on a cold morning.

 

 

[maradona]

On 17/10/2023 at 08:45, numskull said:

How many kms have you driven since you bought it? Have you had a sustained drive for more than 30 mins at working temp > 100km/h? If not try that. 

Arround 2000km in 20 days.

Mechanic says that alternator makes problem or something about it (wires, modules). I hope that he will solve the problem on Friday.

[J.R.]

150km will be the time for another regen if the engine has had the "emissions fix"

 

Have your recent journeys when the problem manifests been less than 30km?

 

Do the radiator fans continue to run when you switch the engine off?