Caddy - Weird results

[KleinerMuck]

Hello,
I'm new in this forum.
My car is a 2011 Caddy 4motion with CFHF 2.0 81kW diesel engine, with DPF but without catalytic converter.
I bought the car in january this year, and the engine exhaust smells unburnt diesel all the time. As it was winter, first I thought it is the extra heater, but obviously it is not.
I dwonloaded now the VAG DPF app, and checked it today by receiving weird results:
Soot mass calc. = 12,47g
Regen. duration = 0 min.
Distance since last regen. = 37 658 km
How can it be that the distance since last regeneration is that long???
As I'm novice in DPF field, what do you recommend to check first end then next?
Kind regards,
KleinerMuck

[KleinerMuck]

I thought its better to attach screen-shot from VAG DPF app from today

[admin]

That so long distance since last regen can be explained with 2 reasons:
ECU chip tuning with DPF removal
wrong calculation formula in the app

If you're confident that no chip tuning has been applied, we need to understand where is the error.
First: what engine group have you used? CFHF engine isn't officially in the list, but similar engines CHFA CFHC CFHD are present in group 3. The first try should be using the group 3, but if you don't have good results you can try all the other groups.

If you don't set any custom engine group, the app sets itself with group 0 that ins't probably good for you.

[KleinerMuck]

Hello,
Thanks for your reply.

The DPF data reading in my second post was done with letting the App chose the engine group, which then was group 0.

Thus, I did another reading with chosing group 3; see below.

Looking at the new reading, one can see that time and distance since last regen. is counting further.
Temperature values varies, indicating that there is live in sensors.
In opposite, soot mass calc. is "frozen".

I'm quite shure that no ECU chip tuning has been performed on that engine.
The engine is a used replacement engine from a previous company car where I know the company a bit (the staff there wouldn't have been able to do this). That previous owner has done so, I don't believe due to several reasons. There is a possibility that the previous owners son could have done it as a boyish prank, but however I still don't believe.

What I could imagine is that the son has mounted a "empty" DPF with entirely removed internals "for joke" and then removed the DPF from the ECU programming. Might this be a possible explanation for the weird readings? Or is there any data in the readings indicating that this cannot has happened?

By the way, it looks like that the oxy cat which is placed in the upper part of DPF-housing, is working. Can this ever be if DPF has been emptied?

Kind regards

[admin]

The common behavior is that the app can read data with reasonable values or can't read the data showing nd.
It's very rare to see a fixed value, while sometimes it happens to read too high or too low values due to a wrong calculation formula.
I'm not an expert of chip tuning or DPF removal, but in the few cases I saw, the values have been exactly the yours, with fixed soot mass calculated and a big value in the distance since last regen. So yes, my opinion is that the DPF system has been hacked, but I'm not an expert, I repeat.

The argument is critical and, in my opinion, there's also a safety risk behind. Personally I'd like to receive a 100% reliable answer asking to do a diagnosis to an official service who can use the official diagnostic instrument. My app can raise a doubt in you, but to be absolutely sure you should use an official instrument.

[KleinerMuck]

Thanks a lot for your reply.

What do you mean by "critical" and "safety risk" if DPF system was hacked?

And back to a question from my last post:
If my DPF was emptied, can it still be that the Oxy-cat placed above DPF in the same housing is working alright?

Kind regards

[admin]

I mean risk of fire. The standard ECU management is full of safety routines to avoid fire, also in case of sensor or system failures. An example is the forced regeneration after a fixed amount of minutes or km, regardless of all the sensor values. This prevents the clogging of the filter that can produce self combustion and fire. The DPF is a high risk system.

If someone simply disable the regeneration process in the ECU, after some hundreds of km the DPF will catch fire for sure.
Any change in the ECU must be done considering all these fire risk so you have to trust blindly in the chip-tuner and his experience because they don't have an user manual, made by the car maker, to follow.

Second question: I'm not expert in those custom operations, I'm sorry. I don't want to give you wrong information.

[KleinerMuck]

Thanks a lot for your reply and warnings. I'll consider all of it when doing the next steps.
Thanks!

[KleinerMuck]

Hello again,

In the meantime I've used all of engine groups in the DPF App with my engine type CFHF.

The following engine groups work showing consistent results as they could be compared to each other:
- group 2
- group 3
- group 10
- group 11 just not being able to show Oil Ash Residue
- group 16

All other groups including selv chosen, don't work due to not being able to show some or all of parameters ("nd").

I took all of readings in listed sequence within 5 minutes so that DPF temperature was the only value which was varying due to cooling down continously (readings were taken when car was standing still, but engine running).

Of course, all of readings show the same weird results according to the thread above, but at least all of the same parameters were showing up.

Admin, do you want me to upload all of the screen shots of the readings in this thread?