DPF WOES

[talljay]

Hi

So my DPF woes. I had the dreaded EML light come on a couple of months ago. Took to my local garage that is not a MB specialist and he told me DPF blocked, they tried cleaning but would need specialist clean - £490 to remove and clean. So I took the opportunity to buy an IcarSoft and this told me there was an issue with DPF sensor, so removed this, replaced with Bosch sensor and cleaned DPF with some cleaner. This seemed to solve the problem, levels went right down and I checked the regen and that happened at around 300k passively and took numbers back down. Fast forward a couple of thousand miles and EML came back on. DPF is still regenning when it gets to 100% but that is taking 50 miles if that, so its regenning pretty much every day. I have tried the forced regen as believe this burns more soot, but failed to do this, have tried 5 times now and dont intend to try anymore as its quite a long process and doesnt seem to work following the Icarsoft instructions to the letter, seems like quite a few people have had similar issues, as it is regenning anyway - this seems like maybe pointless anyway. So this mornings regen I let finish whilst parked up and did get a lot of whiteish smoke coming from around DPF area, maybe fuel as it uses this to force the process and heat. The car has done 125k miles so maybe the DPF is blocked and just needs a pro clean, sensor readings all seem fine DPF sensor is 0 and goes to 0.04 -0.08 when driving hard, back pressure (i believe EGR) is around 1 bar rising to 4 when driving. No other faukt codes from Icarsoft. So there is a lot of advice on forcing regen, DPF sensors etc - Does anyone know when these things actually fail on w204 2013 OM651 or should they last the life of the car, or have any advice. What I dont want to do is spend the £490 and then still have an issue. I should also say I have seen a slight drop in MPG but nothing significant and could just be age - going from around 55 to 50 on a run

 

[Skd884]

Sell your DIE sel and purchase a petrol MB.

 

[kam09]

Which icarsoft do you have?

 

[Cherrypd]

I had this with my old SAAB 93 TTID. Research showed that the DPF is classed as a lifed item. There will become aa point when a new one has to be fitted. Ouch.

 

[Supernoodle]

4 bar back pressure? That's way too high. If pressure really is that high no wonder you have smoke around the DPF, it can't get out the tailpipe.
40mbar differential pressure driving hard? I'd expect that at high idle.

 

[talljay]

Which icarsoft do you have?

V3

 

[talljay]

4 bar back pressure? That's way too high. If pressure really is that high no wonder you have smoke around the DPF, it can't get out the tailpipe.
40mbar differential pressure driving hard? I'd expect that at high idle.

 

[talljay]

So 1 bar idle for exhaust back pressure B60 rising up to a max of around 4 when gunning it, this is right according to research I have done. Idle should be anywhere between.65 - 1.5 and 3.4-4 at 3000 rpm Happy to be told wrong though. The smoke on regen was when stationary so exhaust back pressure at its lowest. 0 bar on idle for dpf and around 40-80mb at 3000 revs on B28/8 (just checked again)

 

[talljay]

V3

V2 actually - just rechecked

Sell your DIE sel and purchase a petrol MB.

lol

 

[talljay]

I had this with my old SAAB 93 TTID. Research showed that the DPF is classed as a lifed item. There will become aa point when a new one has to be fitted. Ouch.

Yer - maybe that is the case, most comments I have found seem to think they are good for 500k km in these but can go earlier

 

[talljay]

4 bar back pressure? That's way too high. If pressure really is that high no wonder you have smoke around the DPF, it can't get out the tailpipe.
40mbar differential pressure driving hard? I'd expect that at high idle.

So 1 bar idle for exhaust back pressure B60 rising up to a max of around 4 when gunning it, this is right according to research I have done. Idle should be anywhere between.65 - 1.5 and 3.4-4 at 3000 rpm Happy to be told wrong though. The smoke on regen was when stationary so exhaust back pressure at its lowest. 0 bar on idle for dpf and around 40-80mb at 3000 revs on B28/8 (just checked again)

 

[kam09]

V2 actually - just rechecked

lol

Ok and is the dpf regen option available at all times or does it only appear once the dpf live data is showing it is nearly full of soot? I have v3 however regen option isn't there at the moment.. not sure if it will appear once the dpf soot fills up in the high numbers..

 

[talljay]

Ok and is the dpf regen option available at all times or does it only appear once the dpf live data is showing it is nearly full of soot? I have v3 however regen option isn't there at the moment.. not sure if it will appear once the dpf soot fills up in the high numbers..

To get it to regen forced by Icarsoft has been impossible. However it is passively regenning on its own when it reaches 100% fill but that is daily, which is clearly an issue

 

[Supernoodle]

~2.5 Bar EBP I would expect is more normal at high loads. Spikes higher during an accel I can understand though. 4 just sounds high, but I guess I don't have the Om651.

Still wouldn't expect any smoke near DPF Something has leaked onto it?

What code came back?

What does the differential pressure reach just before it goes into regen?

 

[talljay]

~2.5 Bar EBP I would expect is more normal at high loads. Spikes higher during an accel I can understand though. 4 just sounds high, but I guess I don't have the Om651.

Still wouldn't expect any smoke near DPF Something has leaked onto it?

What code came back?

What does the differential pressure reach just before it goes into regen?

No codes. The only code pre regen was related to DPF full, no other codes after I swapped the sensor.

I don’t believe the dpf sensor reading is any different pre regen but I’ll check tomorrow when it does yet another regen !

 

[talljay]

Ok and is the dpf regen option available at all times or does it only appear once the dpf live data is showing it is nearly full of soot? I have v3 however regen option isn't there at the moment.. not sure if it will appear once the dpf soot fills up in the high numbers..

To force it you need to go into the service option on v2, not sure if v3 the same and not diagnostics view data section

Once you are in there you have two options to either force Régen whilst driving or anew fill level dependant on what % you are as you cannot do driving regen if you are over a certain level

I have tried the forced regen now 5 times and failed 5 times, but I don’t think this is going to change anything anyway as the car is doing a regen of its own accord when at 100%

 

[kam09]

To force it you need to go into the service option on v2, not sure if v3 the same and not diagnostics view data section

Once you are in there you have two options to either force Régen whilst driving or anew fill level dependant on what % you are as you cannot do driving regen if you are over a certain level

I have tried the forced regen now 5 times and failed 5 times, but I don’t think this is going to change anything anyway as the car is doing a regen of its own accord when at 100%

Yeh I don't have the option showing under service or diagnostics however my fill level is below 35% at the moment..

 

[WilliamParsons]

The 4-bar back pressure is excessively high, potentially causing smoke around the DPF due to inadequate exhaust flow. A 40mbar differential pressure during hard driving is unusual and may be expected at high idle instead.

 

[WilliamParsons]

Your exhaust back pressure readings of 1 bar at idle and a maximum of around 4 when accelerating align with the research you've done. Typically, idle back pressure falls between 0.65 to 1.5, while it should reach 3.4 to 4 at 3000 RPM. The smoke observed during a stationary regen, when the exhaust back pressure is at its lowest (0 bar), is noteworthy. Additionally, your DPF pressure readings of around 40-80mb at 3000 RPM on B28/8 seem to be within expected ranges for your vehicle.

 

[Supernoodle]

No codes. The only code pre regen was related to DPF full, no other codes after I swapped the sensor.

I don’t believe the dpf sensor reading is any different pre regen but I’ll check tomorrow when it does yet another regen !

If it's still only reaches 80mbar that's too low to be restricted. Does soot load in g suggest anything different?

Typically, idle back pressure falls between 0.65 to 1.5,

It's always shown as gauge, so 0.65bar would be less than atmospheric? How does that happen?