Fans going and fast idling [Resolved] DPF Regeneration

[Jast6project]

Good evening you lovely people
I am in need of some help , I have a MY 2018 t6 lwb 2.0tdi chxa engine code ,, I purchased the van about a month ago all good drive fine , since then the speed limiter has been upped bar that nothing , the issue I’m having is I I did a 70 mile journey no warning lights all seemed good until I pulled up at a stop to find the cooling fans going nuts and it smelt warm although temp gauge read 90 on the dot , when I got home I scanned for fault codes found egr temp sensor c curcit issue turned out the plug up on the bulkhead wasn’t clicked home and had come loose fixed no more code, it been two days since the reconnection van seems to drive ok but idle stays high just under 1000 stop starts no longer working and even on short journeys somethings the fans are going flat out when I pull up , no fault codes are registered no fault light on the dash.
One thing i do see in the Dealer invoice history for this van is three water pumps in the space of 50k miles ( this strikes me as a little odd but nothing to mention why it was changed)
Sorry if I’ve waffled on but it’s a very odd fault answers on a post card

 

[DaveD]

van seems to drive ok but idle stays high just under 1000 stop starts no longer working and even on short journeys somethings the fans are going flat out when I pull up , no fault codes are registered no fault light on the dash.

Those symptoms would suggest it is carrying out a DPF regeneration, i'e. burning off the soot in the DPF. If that's the case it is nothing to worry about.
Has it done that after a long run?

 

[Higgidav]

Yes it’s doing a regen. Just let it finish and the revs will return to normal.

 

[Jast6project]

Those symptoms would suggest it is carrying out a DPF regeneration

Yes it’s doing a regen. Just let it finish and the revs will return to normal.

i hope you guys are right being new to me it’s making me nervous , these don’t suffer from cooling fan control modules like the older golds and Audis did ??
, i'e. burning off the soot in the DPF. If that's the case it is nothing to worry about.
Has it done that after a long run?

I did a DPF pressure check it’s at about 0.5 psi when it showed up the egr temp sensor fault at the weekend , so unlikely it feels it’s needed , bar that I wouldn’t expect it to try on a stop start short journey , it is a bluemotion model

 

[Jast6project]

Yes it’s doing a regen. Just let it finish and the revs will return to normal.

I will check the pressures again tomorrow maybe take it for a run see what happens , I’m surprised it will try to regen within a couple of miles of a cold start

 

[DaveD]

I did a DPF pressure check it’s at about 0.5 psi when it showed up the egr temp sensor fault at the weekend , so unlikely it feels it’s needed , bar that I wouldn’t expect it to try on a stop start short journey , it is a bluemotion model

If you haven't already, drive it hard for at least half an hour, keeping the revs over 3,000 even if that means holding it in a lower gear.
If it still does it afterwards you might have a problem.

 

[Jast6project]

Really nervous about driving it hard , I did a 200 mile round trip at the weekend easy 60 minutes at 60mph or more ,that was when the fans first did the flat out when I switched off , now they are going nuts just after 2 mile stop start local trip

 

[Alster]

Sounds like it’s just trying to do a regen.

 

[Deaky]

If it’s part way through a regen when you stop it will start to regen straight away on the next journey.

 

[Jast6project]

Thanks everyone you’ve eased my mind I will take it for a run tomorrow and post a follow up , these are so much more sensitive than my old t4 and 10 times more expensive to fix

 

[roadtripper]

Really nervous about driving it hard , I did a 200 mile round trip at the weekend easy 60 minutes at 60mph or more ,that was when the fans first did the flat out when I switched off , now they are going nuts just after 2 mile stop start local trip

About 200 miles is what I get between regens.

If you are start stop then just get into the habit of letting it stop itself when you pull up. If it doesn't stop and the revs are about 1000 then it's doing a regen and best to let if finish if you can.

Quite why the entire industry think it's helpful hiding all this behaviour rather than just putting an indicator on the dash/screen is beyond me.

 

[Mercsl]

Thanks everyone you’ve eased my mind I will take it for a run tomorrow and post a follow up , these are so much more sensitive than my old t4 and 10 times more expensive to fix

bear in mind that it wont do a regen if below a quarter tank of fuel

 

[Jast6project]

Thanks everyone for your input ,I guess you guys where all spot on from the following day everything returned to normal ,, thanks again everyone who responded