Recurring DPF warning after cleaning and new injectors

[wgerven]

Hi all,

Thanks for taking the time to read my post. I'd really appreciate hearing your opinions.

I have a 2012 Peugeot 5008, 1.6HDI engine. Currently I'm at 203.000 km.

My daily commute is basically twice a 40-minute drive, half highway/half city.


The Problem

About 10.000km ago, I started to get intermittent DPF regen warnings. This continued to the point that no any "regen drive" would actually clear the warning anymore.

I brought it to a mechanic, they dried forced regen, but this proved ineffective, after which they took the DPF out, "cleaned it" (there's no quantitative measure of before/after, so I guess "something" happened), and replaced also the differential pressure sensor.

After the cleaning, it was OK for a short while, but then the warnings came back. Maybe within a week.

In the mean time, I also got a check engine light, and one day, the engine simply didn't want to start anymore.

I brought it to my usual garage, and they determined that the injectors were basically junk, this was at 197.000km. (They had already been worked on at 140.000km, when I experienced limp mode suddenly while overtaking).

So, I got new injectors. The garage told they couldn't find anything off regarding the DPF, but hypothesized that my old injectors could produce excessive smoke and overload the DPF.

After that, I did an hour-long regen drive, highway mostly in fifth. The warning cleared, and for about 5000km there was no dpf warning and I was happy.

However, since, the warnings have returned with a vengeance. Basically, the patterns is as follows: During my morning drive, I manage to clear the warning. Then, during my afternoon drive I have to climb a steep hill on the highway, which I do in 4th at 90km/hr (that's 2800rpm), and without a exception this will trigger the warning. Which I'll then proceed to clear the next morning. In other words: calm/typical driving doesn't trigger it, but high load and acceleration do.

The Question

Today I came across this post: viewtopic.php?t=73050

This was basically the first time that I read that my DPF may actually have a lifetime of 125.000km. And that maybe you can add another 80.000, but that's basically where I'm at with my car... I also know that cleaning a DPF can only do so much, and that you cannot bring it back to new.

I do wish to keep the car. The engine is for the rest in perfect condition, and I enjoy driving it, there's no noticeable oil consumption.

So, I wonder: Perhaps I should actually just replace the DPF since it's beyond its lifetime?

And what would be the diagnostic process leading up to drawing that conclusion? For instance, what about

- bad injector coding,
- boost leak,
- EGR stuck open,
- MAF error,
- turbo control issue,
- thermostat too cold,
- excessive oil burning,
- compression problem.

Can this all be handled/checked off by a simple diagnostic pass over the engine?

I'd really be thankful for your thoughts.

Regards,
Willem

[Stickyfinger]

For what it is worth...

- bad injector coding,...can be checked by Pug Planet software
- boost leak,...values can be read with "live Data" on a test drive using the Pug software
- EGR stuck open, ...operation can be checked with "live Data" on a test drive using the Pug software
- MAF error, ...values can be read with "live Data" on a test drive using the Pug software
- turbo control issue, ...values can be read with "live Data" on a test drive using the Pug software
- thermostat too cold,...values can be read with "live Data" on a test drive using the Pug software or just replace with a new one to be sure.
- excessive oil burning,...not sure but simple consumption reading will help, other maybe have input.
- compression problem...Garage can check this

Was the system fully "Reset" using the correct software and in all the required sub menus after the work was done by the garage....??

[Huskyxantia]

This might sound werid but theres a chap who lives not far from me he was having similar issues, short version , turns out the clutch was slipping on his car ,he had that all renewed i spoke to him about a week ago as he saw me working on my 2008 , he told me his problems have gone since having the clutch replaced

[windy1603]

I had a similar issue on my old DS3 e-HDI after injector failure. I thought I would pressure-wash it to see if it would work again short term until i could replace DPF.

Dropped off the DPF and backflushed it with a pressure washer. It took a while and i think the unburned fuel had mixed with the soot as I had black/orange strings of sludge (like silicone from a silicone tube) coming out of the matrix; after a while, it cleared about 90% of the matrix.

Left to drain overnight and then refitted, and after a bit of steam it was fine; passed 2 further MOTs with 0 smoke readings and 45K miles later, when I sold it is was still running fine.