I've read up on the DPF before, but didn't think I'd get an issue due to the driving I do... but alas it has shown its head. I've had the car a month but not driven it too much. 1.6 Punto Evo Sporting.

I've been doing a mixture of short journeys, 20 mile commutes (30-40mins) and some motorway driving.

The light came on, after a 30 mile motorway journey. That's what my issue is, as I'd expect it with short trips but not on the commute I do nor on the motorway. Questioning if it's the car or my driving as I like to keep the revs low, but found out in the car manual that it wants something around 40mph and 20000 revs for 15mins to get the necessary heat for Regen.

Going to try and follow the instructions and rev it higher for some time on the motorway tomorrow, will update.

Questions being:

Would you consider it to be a problem if the light came on when in 6th gear, trundling along at low(ish) revs on the motorway?

Once regen is complete, how long before it comes back generally.

If I ignored the light, and didn't go on a special trip to Regen the DPF... I've read the car will either stop, or go into limp mode (what are the symptoms of limp mode)

h0sep1pe said:

I've read up on the DPF before, but didn't think I'd get an issue due to the driving I do... but alas it has shown its head. I've had the car a month but not driven it too much. 1.6 Punto Evo Sporting.

I've been doing a mixture of short journeys, 20 mile commutes (30-40mins) and some motorway driving.

The light came on, after a 30 mile motorway journey. That's what my issue is, as I'd expect it with short trips but not on the commute I do nor on the motorway. Questioning if it's the car or my driving as I like to keep the revs low, but found out in the car manual that it wants something around 40mph and 20000 revs for 15mins to get the necessary heat for Regen.

Going to try and follow the instructions and rev it higher for some time on the motorway tomorrow, will update.

Questions being:

Would you consider it to be a problem if the light came on when in 6th gear, trundling along at low(ish) revs on the motorway?

Once regen is complete, how long before it comes back generally.

If I ignored the light, and didn't go on a special trip to Regen the DPF... I've read the car will either stop, or go into limp mode (what are the symptoms of limp mode)

Click to expand...

If it's the amber light that looks like an exhaust blowing smoke, that is just an indication that a regen is in progress. This agrees with your journey description. You need to keep driving at reasonable speed until it goes out. See the PF supplement in the GP downloads section
https://www.fiatforum.com/downloads.php?do=download&downloadid=157

Robert G8RPI.

g8rpi said:

If it's the amber light that looks like an exhaust blowing smoke, that is just an indication that a regen is in progress. This agrees with your journey description. You need to keep driving at reasonable speed until it goes out. See the PF supplement in the GP downloads section
https://www.fiatforum.com/downloads.php?do=download&downloadid=157

Robert G8RPI.

Click to expand...

Thanks for that Robert.

Yeah the light came on after getting back in the car (after the 30 mile motorway journey) and then I the return journey back home with the light on all the way. However I wasn't aware of the 2000rpm requirement, so took the 30 minute motorway journey back home like I would usually drive but the light didn't go off... ?

No luck.

DPF light still on after a 30-40min motorway run in a mixture of 4th and 5th gears. Now sat on driveway idling to see if that finishes it off.

Fuel level doesnt matter does it? I'm a bar above red.

Might have to get a ECUscan, would you recommended any. That can force a regen and pick up fault codes from pressure sensors or something.

h0sep1pe said:

No luck.

DPF light still on after a 30-40min motorway run in a mixture of 4th and 5th gears. Now sat on driveway idling to see if that finishes it off.

Fuel level doesnt matter does it? I'm a bar above red.

Might have to get a ECUscan, would you recommended any. That can force a regen and pick up fault codes from pressure sensors or something.

Click to expand...

If the low fuel light is on it probably won't regen
Allthrough if you did a 30 mins drive I'd imagine it wasn't on all the drive before?
It should have completed to regen in that time
Perhaps try some additive to help teh regen reddex do one
Then try a static regen if it still doesn't complete you probably be looking at having it removed and cleaned

The other and less obvious problem that I have heard a lot of recently is that the pressure sensor for the DPF, that controls the regen and the light coming on is prone to over pressurising and then breaking in heavy acceleration, this means that you can spend a lot of time faffing about trying to fix a DPF problem for it to actually only be a £15 sensor.

It’s defiantly worth getting some proper diagnostic software before paying to swap parts

chris3234 said:

If the low fuel light is on it probably won't regen
Allthrough if you did a 30 mins drive I'd imagine it wasn't on all the drive before?
It should have completed to regen in that time
Perhaps try some additive to help teh regen reddex do one
Then try a static regen if it still doesn't complete you probably be looking at having it removed and cleaned

Click to expand...

AndyRKett said:

The other and less obvious problem that I have heard a lot of recently is that the pressure sensor for the DPF, that controls the regen and the light coming on is prone to over pressurising and then breaking in heavy acceleration, this means that you can spend a lot of time faffing about trying to fix a DPF problem for it to actually only be a £15 sensor.

It’s defiantly worth getting some proper diagnostic software before paying to swap parts

Click to expand...

Thanks both.

I've ordered a ECU plug, so will get that plugged in and download the software when that arrives. Check % blocked, pressure sensors, error codes if software allows it etc.

Took it for another run in 4th for 30mins at 2800rpm with a bottle of DPF additive and Super Diesel. Still light is on.

I did however decide to do some 'boy racer' hard acceleration on deserted Dual carriageway and going hard from 30mph in 3rd gear - then changing into 4th resulted in black smoke from the exhaust. Nothing huge, but could see it from the rear mirror when looking back (I wouldn't have noticed otherwise)
-- Now then, there's mixed messages about that on the internet. Some say that it means the DPF is f**d, some say that it's required (the hard acceleration=black smoke) just to dislodge the soot and get the regen going.

Apologies, I've not owned a Diesel before nevermind one which has a ballache that is a DPF.

The main issue with the DPF is no different to any other filter, the only issue is most filters people throw away.

Also the DPF on your car is also the catalytic converter.

So two expensive lots of gubbins in one tin can.

In some applications DPFs are made and designed to be taken off the vehicle and literally washed out and put back, I don’t think this would work with a car DPF because they are not designed in that way but there are chemicals you can buy and soak the filter, which will dissolve the soot and wash out Most of the loose dirt then you just rinse it through with cold water.

Righto then.

Went and bought myself a scanner and MultiECUscan, managed to figure all that out without much hassle and plugged into the ECU.
No fault codes at all, which I found strange (the DPF light still on) and then had a look through the parameters surrounding the DPF.
Photo attached.



As you can see, 200% plus on the clogging and 'Overload'.... nasty.
Unsure about the pressure sensor at 0mbar.
Decided to give it a go at a Forced Regen, and what do you know, it worked! Bringing down the parameters as below. This does show the sensor at -2mbar. I don't know if that means it's working as it should.



Lovely blueish smoke coming out of the exhaust during the regen, got a few funny looks up and down the street with the smoke and engine revving so high.


The one thing I found interesting. Wrong interesting. Was that the EGR 'actual' and 'desired' were quite far apart, wondering if that's simply down to running cold.

Will see if it clogs up again, and how long it takes before diagnosing further. Could still be a dodgy sensor or EGR allowing too much rubbish into the DPF.


I'm still wary, however. That the car didn't Auto Regen on my trips up and down the motorway. This was at roughly 2500rpm in 4th so the exhaust should've got up to the required temperature after driving for over 40mins (compared to the force regen of 3000rpm for about 8mins). What's up with that.

Well done! I'm wondering what other users think about the discrepancy between EGR 'actual' and 'desired'.

I'm triggered to do some MES measuring as well since it feels like my engine is misfiring sometimes under conditions where the EGR will be open (3rd gear 1400-1500 rpm ~10%-30% throttle)

I wouldn't be surprised if my EGR is caked up after 175k kilometers.

What’s interesting on there is the number of regenerations, only 2 in the life of the car and one of those I’m guessing if the forced one you’ve performed.

I dunno what mileage you have but I’d effect a car that’s at least 7 years old now to have regenerated more than that

From what the MES information said, that number is based on number of 'Forced' regens

The light has returned. Not had the chance to plug in yet, will do that tomorrow.

Done 250 miles before it came back on,
- Started at 63% 'clog'
- Majority of runs have been 20 mile commute (roughly 30-40mins) mix of 40mph A road and urban traffic.
- A few short runs to the shops

Now I'm no expert, but that should surely not clog it up so fast.

Going to have to diagnose further. Maybe it is a faulty EGR, any words of wisdom as to what else it could be?

Might be injectors that are worn out but that's just a guess. What is the mileage on your car?

Detroitdiesel said:

Might be injectors that are worn out but that's just a guess. What is the mileage on your car?

Click to expand...

125,000

Yes, that's a lot! Probably quite a few things wearing out, but would like to make sure I'm fixing the right thing. Read up that there's a variety of potential causes - So it's just checking each one without spending the earth nor lining the pockets of the local garage.

Took it for a spin with the MSE running to create a graph of how the EGR reacts to how it is driven. I'm hoping somebody can run their eye over it, as I'm not sure if it's screwed.

- The EGR 'desired' is coming out at '-0.40mm'.... (yes, a negative number?). Should be a green line right at the bottom of the graph but it got overlayed.

- EGR 'actual' seems to fluctuate very little. Basically from 0.00mm to 0.03mm

- Did urban driving, and some high rev blasts up and down a dual carriageway. Didn't make a obvious difference to the graph.

-Both the parameters surrounding valve opening (%) and position control are not being picked up.

Starting to pull my hair out a little. Why is it a negative number, if that's normal then I assume the valve is either stuck open or closed?

https://imgur.com/HgFGhNJ

Bumping this up, as I've now been driving with the light on since it came back (so a good 4 months, and 5k miles) and I've had no issues *touch wood* other than it still being a bit smoky under hard acceleration and start-up.

So that throws another spanner doesn't it? Surely the car would go into limp at some point. Any ideas would be great, if you're new to the thread take a look at my MultiECU Scan photos