DIESEL PARTICULATE FILTER - Problems...

[T14086]

You an get a maf from Cuffys

They said they didn't know what I was talking about Got a nice deep fat fryer though!

 

[grimwau]

i highly suspect it's not a fault with the system but more something that's car specific. visiting a different dealer may find a fault that was overlooked.

Have to agree on this point as I have a similar problem on my 500 but no-one else with a 1.3MJT on the 500 forum has had the same problems, or if they have they are to a much lesser degree even though some of them do more city driving than I do.

but if the car isn't fit for purpose then the dealer/fiat uk should be a lot more proactive in helping you.

Half right in my case, the dealer hasn't been able to identify my problem and doesn't seem particularly interested in sorting it out but Fiat UK CS have been tremendously supportive and I personally think that they are as good as Lexus in their support role.

 

[volvo_saint]

Dealer took in the car to check out the Mass Airflow Meter and Intercooler.

Found nothing wrong. Car is in perfect health....

My fuel consumption is slowly increasing from 7.3L per 100km to 7.6L.

When it reaches 7.8L thats when normally the DPF triggers a fault. So the car is due for a breakdown soon...

The fuel consumption increases due to the backpressure of the DPF....or many more DPF generations which use fuel...

Interestingly enough everytime they do a forced regeneration they check the oil level and viscosity of the oil. Does this mean that they are concerned that fuel is leaking into the sump?

 

[grimwau]

Interestingly enough everytime they do a forced regeneration they check the oil level and viscosity of the oil. Does this mean that they are concerned that fuel is leaking into the sump?

The extra fuel injected into the engine post combustion is not burnt completely and the residue bypasses the piston rings "borewash" and passes into the sump increasing the level and decreasing the lubrication properties. The ECU monitors this and warns you to change the oil when certain parameters have been met. My oil level increases by approx 1.1ltrs in the time between the oil change and the warning light/message coming on.

Fiat techs are aware that when changing the oil the level should be 2MM below maximum on the dipstick on any diesel engines fitted with a DPF.

 

[Most Easterly Pandas]

Fiat techs are aware that when changing the oil the level should be 2MM below maximum on the dipstick on any diesel engines fitted with a DPF.

Surly they should lower the max on the dipstick by 2mm then.

Or even have several marks on it like 'Max at oil change refil' and an 'Ultimate max'

 

[Caravadossi]

... I have read that these DPF items are causing problems ...

Given that I’ve only recently upgraded(?) from a petrol to a diesel engine, and already fretting about DPFs & `regeneration’ etc – I discovered the following offering from autotrade guru (& FIAT 500 owner) Honest John …


DIESEL PARTICULATE FILTERS, flashing glowplug lights, flashing 'depollution system' lights, engine oil contamination. Please explain.

The latest bain of a diesel driver's life is the Diesel Particulate Filter. On passive cycle the DPF will require the car to regularly be driven significant distances at 2,000rpm plus for the DPF to get hot enough to regenerate and burn off the particulates in it.

DPFs also have an 'active' cycle where additinal fuel is injected into the combustion chambers to creater hotter than normal exhaust gases to burn off particulates in the DPF. However, this does not always work and the extra fuel can instead find its way into the engine sump, contaminating the lube oil and sometimes leading to such a rise in sump oil level that the engine can start to run uncontrollably on its sump oil and will self-destruct.

Peugeot/Citroen/Ford diesel engines don't need to get quite as hot as diesels in other makes because they use an additive to help regenerate the DPF. This used to be added to a tank under the back seat, but is now contained in a bladder that needs to be replaced around every 100,000 miles.

From a Vauxhall Owner's Forum, but generally very helpful advice that applies to most first generation self-regenerating diesel particulate filters ('closed loop' DPFs are more sophisticated):-

Question: The glow plug symbol is flashing. Why? What should be done?

Answer: The DPF regeneration has not been completed during normal driving and now DPF has reached its maximum saturation at which it can still be regenerated. The limit value depends on variant and Model Year, but is in the range of 105% - 125%. Possible causes for this are:

a.) Frequent short distance journeys, i.e. high soot loading while at the same time regeneration of the DPF does not take place because the conditions necessary were not fulfilled.

b.) Frequent interrupted regenerations, i.e. the engine was switched off during regeneration. Applies to short journey drivers who have at least fulfilled the conditions for triggering regeneration. If the glow plug light flashes, the vehicle

a.) Engine running since start for longer than 2 minutes.
b.) Calculated saturation higher than 80%.
c.) Coolant temperature over 70°C for at least 2 minutes.
d.) No DPF-relevant faults stored in system.
e.) A defined vehicle speed threshold must have been exceeded (e.g. for >80% loading, 100 km/h)

Question: Under what conditions is regeneration interrupted/ended once it has started?

Answer: Normally when regeneration has been successfully completed, or:

a.) After a maximum regeneration time (20 - 25 min.).
b.) If the engine is switched off or has stalled.
c.) If the engine is left idling for a long time (5 - 10 min.).
d.) If 1000°C is detected by the exhaust temperature sensor.
e.) If during regeneration, a fault is detected on the components relevant for combustion (injection/intake system). If a regeneration is interrupted once started but before it has been 50% completed, the glow plug lamp flashes on the next engine start (cold or hot) and regeneration begins again once the operating conditions (see 3) have been fulfilled.

Question: How long does complete regeneration take? a.) In the most favourable case? b.) In the least favourable case?

Answer: a.) Under constant conditions, i.e. the exhaust temperature necessary for regeneration always lies above the required value, for example during motorway/cross-country driving, the average regeneration time is 10 minutes.

b.) Vehicle conditions such as long down-hill descents, frequent driving in the low-load range (city driving, idling) allow the exhaust temperature to fall. If the conditions for triggering regeneration were fulfilled, the active regeneration time can be extended up to 25 minutes (depending on engine type). If complete regeneration is not possible within this period, the regeneration will be interrupted.

Question: How does regeneration affect the oil life?

Answer: On each regeneration or attempted regeneration, a certain diesel fuel amount is injected into the engine oil which reduces the oil life. If the "INSP" light in the instrument cluster comes on, the engine oil is exhausted and must be changed. Failure to do so could damage the engine.

MORE INFORMATION FROM http://www.tdciforum.co.uk

Catalysed Diesel Particulate Filters

Traditional Diesel Particulate Filter systems consist of a filter material positioned in the exhaust designed to collect solid and liquid particulate matter emissions while allowing the exhaust gases to pass through the ceramic walls. Catalyzed Diesel Particulate Filters (CDPF) are designed not only to achieve collection efficiencies of 90% or greater in terms of mass (over 95% when expressed as number of ultra fine particles), but also to burn off the collected particulate matter into carbon dioxide and water. The incorporation of catalytic coating in CDPFs lowers the temperature at which particulate matter burns. To achieve this auto-ignite and the sustain combustion of collected particulate matter CDPFs must attain a minimum temperature of approximately 250C that can be helped by electrical heating if the engine-out exhaust temperature of a heavy-duty engine does not typically achieve this required temperature level.

Ceramic Diesel Particulate Filters

These types of particulate filters must be regenerated. Regeneration of a DPF is to remove accumulated soot/carbon. Two general approaches are continuous and intermittent regeneration. In continuous regeneration, a catalyst is provided upstream of the DPF to convert NO to NO2. NO2 can oxidize carbon at typical diesel exhaust temperatures and thereby effectuate continuous regeneration. A disadvantage of this approach is that it requires a large amount of expensive catalyst. This technique is not commonly used on cars but is found on public transport vehicles / council vehicles.

Intermittent regeneration involves heating the DPF to a temperature at which carbon combustion is self-sustaining in a lean environment. Typically this is a temperature from about 400 to about 700 degrees C., depending in part on what type of catalyst coating has been applied to the DPF to lower the soot ignition temperature. A typical way to achieve carbon combustion temperatures is to inject fuel into the exhaust upstream from the DPF, whereby the fuel combusts generating heat in the DPF or an upstream device. In most modern cars the catalyst is injected into the fuel tank and is effectuated through the fuel injection system.

Here is an extract from the press conference launching the Ford's cDPF system on the new Fiesta.

"Coated Diesel Particulate Filter (cDPF): Ford's optional cDPF system traps carbon deposits as they exit from the combustion system, preventing their release into the atmosphere. Under favourable conditions the system then cleans itself with a controlled 'burn-off' process, thus providing a self-contained clean air system without the need for service maintenance. This system contains a ceramic filter body of around 4 litres volume mounted behind the exhaust manifold plus a special regeneration support unit on the engine's intake manifold. Together these components enable the filter system to regenerate in any possible drive condition automatically without requesting any input from the driver and without compromising driveability noticeably during regeneration.
The advantages of the system are:

* Additive systems have an additional additive tank that primes the fuel tank with the additive (a metallic catalyst) at every refuelling. On the Ford cDPF the additive is embedded in the filter washcoat, hence no additional complex priming system is required and no refilling of the tank.
* Long life – a ‘normal’ additive DPF tank needs refilling after approx 60k km, whereas the new Ford cDPF has been developed to last at least 200.000km."

VAG DIESEL PARTICULATE FILTERS

Courtesy of David Bodily Volkswagen Technical Support Specialist

Diesel Particulate Filter (DPF)

Detailed below is important information outlining the function and features of the Diesel Particulate filter which all members of your team need to be aware of.

Diesel particulate filters are becoming more commonplace on diesel engines, particularly sizes 2.0L upwards. This is in order to reduce the exhaust emissions as required by European legislation.

The prime reason for a DPF is to reduce particulate matter entering the atmosphere. Particulate matter is found in the form of soot, which is produced during diesel combustion. The DPF traps most of the soot which would normally travel down the exhaust and into the atmosphere. The DPF can hold a certain amount of soot, but not a huge quantity and therefore it needs to go through a process called ‘regeneration’ in order to clear the soot loading. When the soot goes through a ‘regeneration’ process it will be converted to a much smaller amount of ash. The ash is non-removable. There are two types of ‘regeneration’, passive and active.

During long motorway journeys, passive regeneration will occur. This needs no intervention from the engine control unit. Due to the raised exhaust temperatures on a long journey (temperatures between 350 and 500°C), the procedure occurs slowly and continuously across the catalytic-coated (with platinum) DPF. The catalytic-coated DPF is situated close to the Engine, therefore the exhaust gas temperature is high enough (500°C) to ignite the soot particles. Due to this soot is burned-off and is converted into a smaller amount of ash.

Active ‘regeneration’ is when the ECU intervenes when the soot loading in the DPF is calculated to be 45%. The procedure lasts for about 5 – 10 minutes. Specific measures are taken by the ECU to raise the engine exhaust temperature to above 600°C, these include switching off the exhaust gas recirculation and increasing the fuel injection period to include a small injection after the main injection. The soot particles are oxidised at this temperature.

The ECU will trigger a regeneration process, if for some reason this is aborted, ie. customer slows down, stops etc, the process will be resumed when regeneration conditions are once again met, above 60km/h (38mph). This will continue for 15 minutes.

If after 2 attempts of 15 minutes, a successful regeneration has not been possible, the loading will increase. At 50% soot loading, the ECU will continue to maintain maximum exhaust temperatures of 600°C to 650°C to cause a regeneration process. The system will try to run a regeneration process for 15 minutes. If unsuccessful, the system will repeat this process for a further 15 minutes, if still unsuccessful, the DPF light on the driver display panel will then be lit.

The owners handbook states, the DPF symbol lights up to indicate that the diesel particulate filter has become obstructed with soot due to frequent short trips. When the warning lamp comes on, the driver should drive at a constant speed of at least 60 km/h for about 10 minutes. As a result of the increase in temperature the soot in the filter will be burned off. If the DPF symbol does not go out, the driver should contact an authorised Volkswagen repairer and have the fault rectified.

At 55% soot loading the DPF light is lit on driver display panel. At this point the customer should follow the advice in the handbook. If they ignore this information and continue driving the vehicle until the soot loading reaches 75% without successful regeneration, additional warning lamps will light up. At this point the customer will also be complaining of lack of power, etc.

At 75%, regeneration is still possible with the use of the VAS tester. Only when the loading is above 95%, is it necessary to replace the DPF unit.

Operating Status System Response
45% DPF Load Level 1
- Normal Regeneration
50% DPF Load Level 2
- Regeneration at maximum exhaust
temperatures
55% DPF Load DPF lamp
Regeneration from 60 km/h
onwards
("See operating manual")
75% DPF Load DPF, SYS and MI lamp
Torque limitation, EGR
deactivation,
Regeneration via VAG tester only
95% DPF Load Replace the DPF Unit

The Warranty department has confirmed that if there is no fault on the vehicle and DPF regeneration has been unsuccessful due to the customers driving style and the customers failure to comply with the instructions in the handbook, DPF replacement will not be paid for by warranty.

Common causes for complaint

• Frequent short journeys – Regeneration conditions are not met.
Not recommended for sale in the Channel Islands and inner city driving.

• Customers who continue to drive the vehicle with DPF light on – Continued
driving with the DPF light on and without successful regeneration results in
excessive soot loading of the DPF, to a point where it is above 95% loaded.
At this point regeneration is not an option and replacement of the DPF is
necessary.

• Fault 18434 particle filter bank 1 malfunction – Common fault code. This does
not only relate to the DPF itself, but the entire exhaust gas handling system. This
can be caused by defective temperature sensors, pressure sensors, additive
system components (if applicable), poor connections, wiring issues, etc.

Important Information

• Before diagnosing a problem vehicle or attempting to perform an emergency
regeneration, it is important to obtain a full diagnostic log and read out relevant measured value blocks. These MVB’s contain important information on the condition of the DPF system and are essential in diagnosing the fault. When the DPF light is illuminated, it does not necessarily mean that the DPF requires regeneration. For further advice, please contact Technical Support with the information from the diagnostic log and MVB data.

• If a problem vehicle arrives with the DPF light, the engine management light and the emissions light on. If during your diagnosis and reading of relevant MVB’s, you find that the soot loading exceeds 75% (but is still below 95%), an
emergency regeneration procedure must be performed with the VAS tester.
Further to this, the customer needs to be educated. They need to understand
why the lights have appeared on the dash panel. Their attention needs to be
brought to the owners handbook instructions, so that they are aware of what the DPF light means and what to do when it appears. This should prevent
unnecessary repeat visits for regeneration purposes.

David Bodily

Volkswagen Technical Support Specialist

Source: http://www.honestjohn.co.uk/faq/faq.htm?id=130


Can anyone post something more detailed than the generalisations given in the FIAT Owner Handbook?
.

 

[D4nny8oy]

Surly they should lower the max on the dipstick by 2mm then.

Or even have several marks on it like 'Max at oil change refil' and an 'Ultimate max'

Judging by the number of vehicles we have come-in with no oil registering on the dipstick, most Fiat/Alfa owner's don't know it's there- so why complicate matters with multiple 'MAX' levels?

 

[volvo_saint]

The overview on DPF issues with other vehicle manufacturers is pretty good.

Unfortunately FIAT are not interested in my problem. They asked me to bring my vehicle to the garage and I was charged 50 quid for the check up on the intercooler and mass airflow meter....

As my wife picked up the car she was not aware to contest that charge as it was DPF related.

So this vehicle is proving costly run....with a forced regeneration every month I have to pay for....

 

[Most Easterly Pandas]

so why complicate matters with multiple 'MAX' levels?

Its hardly that complicated.

Some autos have this on their gearbox dipsticks.

 

[D4nny8oy]

Its hardly that complicated.

Some autos have this on their gearbox dipsticks.

You're ignoring the subtle sarcasm in my post.

 

[DaveMcT]

The Fiat DPF shows two warning modes. When it starts to flash you should drive the car on the regeneration cycle. Which means about 30 miles at motorway speeds. This gets the exhaust hot so the particles are burnt off. This is covered in the user manual.

If you ignore the flashing lamp the filter will eventually clog and the system will eventually go into limp mode and the lamp is on continuously. This is also made clear on the car's user documentation. Cleaning it out becomes a service cost.

ll makes of car with DPFs are the same in this respect. Fiat, VW, Ford, Pug, etc.

When a car is used normally with the odd longer run the regeneration happens without the driver being aware. But if the car only does short commutes and shopping trips and never gets hot, the filter will get clogged and need a special journey to regenerate it.

Stuart H makes a very good point. Short runs are bad for any car (Fiat or any other make) and the owner should really be using a bike bus or electric car that is suitable for this type of journey.

Short runs are also the most polluting which is why the filter gets clogged faster. At least this way the pollution isn't thrown into the town for the people on bikes/foot to breathe. Petrol cars dont have a PF but they will do soon enough. Just because they make soot so fine its not visible does not mean its not there.

The latest diesels are the cleanest and most energy efficient engines to own. What a shame the Government have not appreciated that by reducing the fuel duty..

As for LPG... does anyone believe the excise duty wont shoot up as soon as its become a popular fuel.

 

[volvo_saint]

Well - the yellow warning light came on again last week and it was back to dealer for a regeneration for which I had to pay.....

I have officially rejected the car now under the sales of goods act.

Awaiting reply from the dealer.

 

[Most Easterly Pandas]

Keep us updated with how the rejection goes

 

[D4nny8oy]

The Fiat DPF shows two warning modes. When it starts to flash you should drive the car on the regeneration cycle. Which means about 30 miles at motorway speeds. This gets the exhaust hot so the particles are burnt off. This is covered in the user manual.

If you ignore the flashing lamp the filter will eventually clog and the system will eventually go into limp mode and the lamp is on continuously. This is also made clear on the car's user documentation. Cleaning it out becomes a service cost.

ll makes of car with DPFs are the same in this respect. Fiat, VW, Ford, Pug, etc..

Technically not true as there's two versions of DPF- the system that Fiat use on 90% of their vehicles, whereby fuel is injected on the exhaust stroke to heat the catalyst, and Additive-based systems which have a separate tank containing a special fluid which is mixed in with the fuel to help burn-off the particulates when needed- which, in the Fiat range is only on the Ulysses due to platform-sharing with Citroen/Peugoet. The Additive system has a considerable downside in that the hideously expensive fluid is hazardous and needs topping up every 72k (or earlier in some cases).

When a car is used normally with the odd longer run the regeneration happens without the driver being aware. But if the car only does short commutes and shopping trips and never gets hot, the filter will get clogged and need a special journey to regenerate it.

The DPF regeneration process will occur with the vehicle stationary and engine idling, if necessary.

 

[Most Easterly Pandas]

The DPF regeneration process will occur with the vehicle stationary and engine idling, if necessary.

But will normally start when the vehicle is going and engine turning above idle rpm though right?

 

[D4nny8oy]

Usually, yes. But if it detects the filter needs clearing, it'll do it whether it's idling stationary or at the optimum 60km/h or 1800 rpm.

 

[volvo_saint]

Got a reply from FIAT. They will investigate my complaint and inform me within 4 weeks of the result.

Not a lot to investigate - car stops roughly every 700miles...because the DPF is full....

Anyhow - awaiting their investigation.

 

[volvo_saint]

Today the engine warning light came on again. So next Monday its a trip back to the dealer.....

To say that I am disappointed with the way that FIAT is dealing with my case is an understatement. I have to pay for all repairs regarding the regeneration of the DPF - FIAT insist that this is not warranty issue. Although the car is only 21 months old.

FIAT warranty with respect to DPF problems is a disaster. If you buy a FIAT car with a DPF system try to get FIAT to guarantee the DPF system and see what happens....

But when your car is taken off road for DPF problems it means I have no car available apart from forking out money every 4 weeks now to have it temporarily fixed until the next breakdown.

Never again a FIAT....

 

[flyingscot]

Today the engine warning light came on again. So next Monday its a trip back to the dealer.....

To say that I am disappointed with the way that FIAT is dealing with my case is an understatement. I have to pay for all repairs regarding the regeneration of the DPF - FIAT insist that this is not warranty issue. Although the car is only 21 months old.

FIAT warranty with respect to DPF problems is a disaster. If you buy a FIAT car with a DPF system try to get FIAT to guarantee the DPF system and see what happens....

But when your car is taken off road for DPF problems it means I have no car available apart from forking out money every 4 weeks now to have it temporarily fixed until the next breakdown.

Never again a FIAT....

I take it the Sale of Goods act rejection wasn't successful?

 

[volvo_saint]

I am still waiting for a reply from the FIAT dealer - they wrote that I would get a reply by Jan 20th.