Sprinter 311 2.2cdi, excess regen + white smoke + oil level rising

[m80]

I don't know if this applies to the Sprinter,
but on mine the cabling to the differential pressure sensor, mounted on the bulkhead to the rear of the exhaust, suffered from the heat from the exhaust.

It had fallen forward at some point, the cabling had melted, so the readings were intermittently screwed. But only after I had disturbed it.
I soldered in a 3 core patch, and improved the cable run.

 

[tcourtneyvincent]

On this 651 I would have to do a running check.

On my earlier 642 engine at tickover 48hpa, at revs 122hpa.

But if yours is an intermittent fault then you would expect the reading to be acceptable when running correctly. The readings when in fault might give an indication.

Which engine , age is yours?

It's a 646 year 2008. I have lend my scanner to da friend. Getting it back on Monday and going to gather some more data.

I do however have a video I took of the data while the engine was in its other "personality" for lack of a better word! The differential pressure was only between 6-10hpa...

 

[tcourtneyvincent]

I don't know if this applies to the Sprinter,
but on mine the cabling to the differential pressure sensor, mounted on the bulkhead to the rear of the exhaust, suffered from the heat from the exhaust.

It had fallen forward at some point, the cabling had melted, so the readings were intermittently screwed. But only after I had disturbed it.
I soldered in a 3 core patch, and improved the cable run.

So the plug that connects to my differential sensor has the same heat damage. Might have dropped onto the Dpf at some point in its life. It still seems to work tho in as much as it shows a reading on the live data that varies and doesn't throw up any errors. Good point on it being intermittent tho, I will change the plug to be 100%

 

[tcourtneyvincent]

I would consider getting the injectors tested to rule them out? Maybe they're leaking/stuck open and the increased temps in regen cause the smoke.

How are you telling when it's in regen and for how long?

The engine sounds like a different engine all together. It becomes throaty sounding, you can hear the injectors become more clattery and the throttle responce becomes slow along with a slight reduction in power, maybe 5-10%

 

[m80]

Tother thought.
The injectors may have been replaced, or refurbished.
They would then need setting up on Star, although I think the V3 can display the registered (on the ECU) identifications to see if the match those atop the fitted injectors.

On star there is a cleaning programme,
then there is a zero values recalibration at tickover.

I fitted 'new' injectors 20k miles ago. The tickover and low revs were never ideal.
Last week I carried out these 2 adaptations and the improvement is noticeable. At fitting I hadn't cleaned but I had zero calibrated, strange.

There is also a recalibration while running, designed for if there are strange combustion noises, this might fit your complaint. But I would first carry out the other 2 calibrations.

Also strange that at tickover and low revs my running could vary, subtly.

Of course your issue here is having to pay an indie for these works, and not knowing if the result would be beneficial.

Eeee, when a were a lad all yer ad t do were ***** with the points and carb, now there's all this white mans magic inside black boxes.

 

[tcourtneyvincent]

Update -

So it does have a genuine merc DPF fitted which looks like it was manufactured in 2015, so not the original.

I have also noticed an exhaust leak between the Cat and the DPF. Not a major one but enough that you can see a couple black soot lines from where the clamp is deformed and there is soot on the underside of the chassis. I have order another clamp. Its my understanding that if the exhaust pressure is off then the whole Regen can throw it toys out the pram?

Also it's not an original genuine Cat. It's an aftermarket EEC. Could this be throwing things out?

 

[tcourtneyvincent]

Have just plugged in my iCarsoft v3. The differential pressure sensor, back pressure and lambda are varying...

The Differential pressure sits at 12/13hpa on idle for maybe 1 minuet, then increases over the course of a second or two to 17hpa and will stay there in till I blip the throttle, even if only by 100 rpm, then it drops all the way to 10hpa before settling at 13hpa again.

The back pressure and lambda move in unison with this odd behaviour too.

Pics for the figures. Any ideas?

 

[tcourtneyvincent]

Have just plugged in my iCarsoft v3. The differential pressure sensor, back pressure and lambda are varying...

The Differential pressure sits at 12/13hpa on idle for maybe 1 minuet, then increases over the course of a second or two to 17hpa and will stay there in till I blip the throttle, even if only by 100 rpm, then it drops all the way to 10hpa before settling at 13hpa again.

The back pressure and lambda move in unison with this odd behaviour too.

Pics for the figures. Any ideas?

Now the van is in its regen mode. The Dpf sensor has dropped to 1 or 2 hpa (milibar), surely this is too low?

 

[m80]

What's the temperature at the DPF while driving?

 

[tcourtneyvincent]

What's the temperature at the DPF while driving?

Will peak at these temps while driving

Cat - 637 degrees C
Dpf - 576 degrees C

 

[m80]

I would expect the DPF to be passing 600 when driving (unless coasting), even over 700. But that is regen temperature unless, you're hoofing it.
That is high for the cat.

Personally I have found iCarsoft to be less than reliable, can you be sure those temperatures aren't swapped? I would unplug each sensor when cold to confirm.

Otherwise I suggest there is a clue in the cat being hotter.

 

[tcourtneyvincent]

I would expect the DPF to be passing 600 when driving (unless coasting), even over 700. But that is regen temperature unless, you're hoofing it.
That is high for the cat.

Personally I have found iCarsoft to be less than reliable, can you be sure those temperatures aren't swapped? I would unplug each sensor when cold to confirm.

Otherwise I suggest there is a clue in the cat being hotter.

Okay I just unplugged the sensor on the Cat and the reading on the icarsoft shot up to 1200c which I guess is its default, so its reading the correct device. However, I did realise that the temp sensor is just before the DPF, not actually in it. And on the icarsoft it say "sensor upstream of dpf". I'm assuming the fuel hits the Dpf and ignites hence why its supposed to be hotter than the cat, but if the sensor is not in or post dpf, how can it know the temp of its burning??

 

[Supernoodle]

An exothermic reaction occurs in the Diesel Oxidation Catalyst. That's what causes the higher temp post cat, ie DPF inlet. Fuel doesnt reach the DPF.

 

[tcourtneyvincent]

An exothermic reaction occurs in the Diesel Oxidation Catalyst. That's what causes the higher temp post cat, ie DPF inlet. Fuel doesnt reach the DPF.

Right gotcha, thank you. So I need to work out why this reaction isn't happening. Faulty Cat? Not the correct ballance of exhaust gasses?

 

[tcourtneyvincent]

An additional thing.

The van has always done a strange flutter every minuet or so when on idle.

The revs don't change, just the tone of the exhaust note slightly flutters on off on off on off over the course of a couple of seconds.

After playing around with icarsoft I manually turned the egr on and off. It's the same sound and a dpf guy has confirmed the sound is the EGR.

Also, looking at the live data I have seen that the EGR never goes below 5.5 odd percent. Its my understand that the EGR should be totally closed during regen so as to get as much O2 and high burning temp? Could this 5% be throwing the mix out of ballance?

Furthermore, the fluxuation in dpf pressure sensor readings seems corolate with when the EGR flutters

 

[m80]

Is it possible that the white smoke isn't due to over fuelling of diesel?
You may not be in regen but seeing the effects of oil getting into the exhaust, intermittently.
Via the turbo perhaps??

 

[tcourtneyvincent]

Is it possible that the white smoke isn't due to over fuelling of diesel?
You may not be in regen but seeing the effects of oil getting into the exhaust, intermittently.
Via the turbo perhaps??

It's definitely at least trying to regen. Normally temps sit no higher than 200 at idle, currently they will go way above that. In regen it sounds like a different beast, I can hesr the timing of the injectors changes, I can see on the live data the fuel injections cubed figure per stroke (can't rememeber the unit of measurement) jump up from about 4.5 to 7 or 8. It stinks of unburnt fuel and the oil level is rising. Also I thought oil burning is blue smoke not white?

 

[Supernoodle]

Right gotcha, thank you. So I need to work out why this reaction isn't happening. Faulty Cat? Not the correct ballance of exhaust gasses?

There isn't any balancing of gases to do.

During a regen the exhaust temp is usually controlled closed loop, ie not hot enough, increase the post injection quantity, too hot, reduce post injection quantity. If that exothermic reaction isn't happening it would ramp up those post injections trying to get it hot.

Used to see problems with old transits that didn't exotherm. They had both bricks in the same can. There was a temp sensor on the inlet and mid way on the can.

 

[Supernoodle]

An additional thing.

The van has always done a strange flutter every minuet or so when on idle.

The revs don't change, just the tone of the exhaust note slightly flutters on off on off on off over the course of a couple of seconds.

After playing around with icarsoft I manually turned the egr on and off. It's the same sound and a dpf guy has confirmed the sound is the EGR.

Also, looking at the live data I have seen that the EGR never goes below 5.5 odd percent. Its my understand that the EGR should be totally closed during regen so as to get as much O2 and high burning temp? Could this 5% be throwing the mix out of ballance?

Furthermore, the fluxuation in dpf pressure sensor readings seems corolate with when the EGR flutters

If that's an EGR commanded duty cycle I expect 5 is min, 95 max. You really want position feedback, but I think icarsoft doesn't show that.

 

[tcourtneyvincent]

If that's an EGR commanded duty cycle I expect 5 is min, 95 max. You really want position feedback, but I think icarsoft doesn't show that.

I'm pretty sure it's labeled as "position" on the icarsoft