Hi have a Mk2 1.6tdi 12 plate and randomly when car is up to temp the revs at idle are 1100-1200 rpm. Most of the time it sits at around 800rpm. Not ideal for driving around town especially when in first gear as car wants to go faster than car in front. Just wondering if it might be trying to regen the DPF. No lights or warnings etc on dash. Noticed as well that even though temp sits at 90 the cooling fan comes on when I stop engine for about 20-30secs when the revs have been high at idle. Car usually gets a long run from time to time but mostly shorter journeys.

Alasdair

Everything you have said sounds like a regen.

You won’t get a dashlight until it fails multiple regens and the soot level starts to rise. It then means you need to take action.

Usually when I notice the revs sitting on 1,000 rpm I just take it down the motorway a junction and back again in 5th gear. By the time I am home it is idling normal.

Speaking to a mechanic he said the majority of DPF issues people get are people disturbing regens turning the car on and off due to them doing short journeys.

When I got my Octavia it had a an awful remap on it and the VAG correction software. I was getting passive regens every 100 miles.

I had the correction software removed and then a proper custom map. I get them once a tank now. Usually a 400 mile interval.

That’s on Sainsbury’s diesel with a squirt of millers ecomax fuel additive.

If a Euro 5 1.6 TDI CR that has had 'The Fix' & it gets rolled back and a remap there is the flow device in the air intake to remove also.

My similar engine idles at 1000 rpm if the engine has not been run for a few days or in cold weather.

It does that if it sees the battery voltage indicates a recharge needed.

17 hours ago, Ootohere said:

If a Euro 5 1.6 TDI CR that has had 'The Fix' & it gets rolled back and a remap there is the flow device in the air intake to remove also.

Not sure if its had the fix or not. I assume not as car runs very well and plenty power. Have had it for about a year with no probs. Keep meaning to check.

Alasdair

Thanks for the replies. Will go for a decent run next time it happens. Not sure how long it takes to regen but reckon a run at 60-70 for a while should help

Alasdair

Just check if Outstanding or not.

If done probably not showing outstanding.

The Airflow device is simple enough to check to see if fitted.

http://skoda-auto.com/services/recall-campaigns

Edited 2 September, 20252 Sep by Ootohere

Many thanks for the link

Alasdair

3 hours ago, Alasdair1 said:

Thanks for the replies. Will go for a decent run next time it happens. Not sure how long it takes to regen but reckon a run at 60-70 for a while should help

Alasdair

Usually around 15 mins for the cycle to complete.

Sorry if I chose the wrong thread but my 2008 octavia is having ongoing issues regards frequent regens. Almost every drive.

I was thinking along the lines of software because new (Aftermarket) DPF from Germany fitted (all values ok, except for high ash volume)

Full adaptation carried out which reset ash volume, differential pressure still good, soot load miniscule. Exhaust temp sensor before DPF replaced as I thought the reading was a bit low, lower reading than the sensor after DPF. Same readings present with new sensor. (No black soot in exhaust tip)

EGR valve seems to work as it should, cooler doesn't appear blocked, no engine codes ever present.

I will attach a picture from my diag tool stating what software it's running currently (5760)

All the help I can get is welcome cause I'm at my witts end and really don't want to map the dpf out

2 hours ago, Dean_C said:

DPF from Germany fitted (all values ok, except for high ash volume)

Adaption does not not do anything physical to the DPF.

A high ash load unit will always be near end of life.

Perhaps more frequent regenerations needed if the active part of the DPF is too small?

It does, you tell the ECU that the DPF has been replaced and set the oil/ash content to zero.

38 minutes ago, Dean_C said:

It does, you tell the ECU that the DPF has been replaced and set the oil/ash content to zero.

I think what @pikpilot is suggesting is that changing the values in the software does not physically remove the ash.

Changing the values can be useful to cheat the ecu into doing a regen when it won't because it deems ash levels are too high.

The amount of ash does not change that is in the dpf.

Lowering the value can trick the system to do a regen and if the regen is succesfully completed. This can kick the can down the road for a bit longer.

Eventually the ash will need removing physically or dpf replaced.

A dpf is not a cure to diesel being burned inefficiently either, it just catches and stops soot. If a vehicle is doing too frequent re-gens, It's wise to look at the cause not the environmental solution.

Before DPFS it was obvious when an engine was struggling the dpfs hide issues.

25 minutes ago, pikpilot said:

Adaption does not not do anything physical to the DPF.

A high ash load unit will always be near end of life.

Perhaps more frequent regenerations needed if the active part of the DPF is too small?

1 minute ago, Stonekeeper said:

I think what @pikpilot is suggesting is that changing the values in the software does not physically remove the ash.

Changing the values can be useful to cheat the ecu into doing a regen when it won't because it deems ash levels are too high.

The amount of ash does not change that is in the dpf.

Lowering the value can trick the system to do a regen and if the regen is succesfully completed. This can kick the can down the road for a bit longer.

Eventually the ash will need removing physically or dpf replaced.

A dpf is not a cure to diesel being burned inefficiently either, it just catches and stops soot. If a vehicle is doing too frequent re-gens, It's wise to look at the cause not the environmental solution.

Before DPFS it was obvious when an engine was struggling the dpfs hide issues.

DPF has been replaced, stated above.

"If a vehicle is doing too frequent re-gens, It's wise to look at the cause not the environmental solution."

And this is exactly what I'm trying to establish, what is the cause of my too frequent regenerations?

Thanks.

Fuel injector spray patterns incorrect and need cleaning or replacing.

EGR system blocked or not working

Boost pipes split

In fact All the things that you can find about diesel engines putting out clouds of black smoke in the past.

The Dpf just masks the symptoms.