Alfa Romeo Forum banner

1 - 14 of 14 Posts

·
Registered
Joined
·
41 Posts
Discussion Starter #1
I was looking at my parking sensors using fiat ecu scan. While doing this I checked the status of my dpf. It said normal clogging and was 88% clogged. The car is used mostly for short journeys so I am wondering if it would be prudent to force a regen based upon that level of clogging? Cheers
 

·
Registered
Joined
·
146 Posts
i suggest you don't. there was a big discussion about forced regen and guys agree that it rises the temperature dangerously high on the first catalytic converter and if done often could damage turbo! use if only necessary, and in your case it is not necessary yet.
 

·
Registered
Joined
·
7,179 Posts
No, take it up the motorway for half an hour, warm the car up first, then floor it up the slip road, leave it in fourth and stick the cruise on, it should sortbit out and will drop back to about 15 percent.

Forced is a last resort and is a bit scary!
 

·
Registered
Joined
·
31 Posts
If I floor it up the slip road, then stick it in 4th with the cruise on, I'm not sure I will make the roundabout at the top !!
Joking aside (and new to diesel), what is a forced regen - or a normal one for that matter!! :confused:
 

·
Registered
Joined
·
2,428 Posts
If I floor it up the slip road, then stick it in 4th with the cruise on, I'm not sure I will make the roundabout at the top !!
Joking aside (and new to diesel), what is a forced regen - or a normal one for that matter!! :confused:
Hi Modulus (and welcome aboard)

The Diesel Particulate Filter (or DPF) is a hateful device located towards the rear of your exhaust system. It traps soot particles, with the "amount" of trapped soot being measured by a pressure differential. In order to regularly remove this trapped soot, a process called 'regeneration' automatically occurs, where the exhaust temperatures are raised to higher levels (greater than about 600C ). This causes the soot particles to catalyse (effectively "burn out"), thus emptying the filter.

Your car will automatically initiate a regen when required, by injecting diesel during the exhaust stroke, which raises the exhaust temperature.

If you do lots of long journeys, regens aren't likely to be a problem, but if you do lots of short journeys, then you may not get up to a temperature suitable for a regen, or you may complete your journey before the regen finishes. Either way, eventually your DPF will fill up completely and your car will go into 'limp mode'

A 'forced regen' is when you use diagnostic software to force the car to regen whilst standing still. Not recommended for the reasons given above.

To the OP - an "Italian Tune Up" is the best way forward. Periodically take your foot off the gas. If the turbo boost gauge drops straight to zero, rather than 'floating down', then you are in a regen. Also, your fuel consumption will be (even more) abysmal. :thumbs:
 

·
Registered
Joined
·
7,179 Posts
The car has a particle filter or DPF, thisncaptures the soot that diesels generate, leaving a clear exhaust.

It needs cleaned out every 180 to 350 miles and the car knows when it needs done and looks for an opportunity, when the car is up to temperature and moving at a reasonable speed, it then manages the airflow and dumps fuel into the exhaust on the exhaust stroke, this sets up a high temperature burn in the DPF and the particles are burnt off.

It takes about 10 minutes, during which the MPG drops dramatically, the exhaust sounds a bit boomy and there is a burning smell. The turbo gauge will also drop like a stone when you lift off and if you stop, it will will sit at 10% boost, rather than zero.

When this comes on, try and keep the car over 3000rpm till it's over and alter your route so don't need to stop.

If you drive the car in town a lot, you might see it generate a warning that it needs cleared, I.e take it for a run as I described.

A forced regen is dome with diagnostic software and it's for cars that have been unable to regenerate on the road and are now too blocked to do so, ideally it needs physically checked over before doing so, also the car sits revving it's nuts off for 15 minutes, belching smoke with a glowing orange exhaust, it's not a sympathetic process and should only be done if absolutely necessary, and always with the bonnet open as it needs to vent a LOT of heat, it can melt the paint from workshop floors......so do it outside if at all.

You might read about a lot of issues on here with these systems, but believe me, Of DPF diesels of this age, the Fiat system is probably the most reliable and best.
 

·
Registered
Joined
·
31 Posts
Great answers from both of you, thanks. :thumbs: I have a 70k mile, 210bhp 2.4 ti and I keep reading about regens but I have never noticed any of the regen signs. I get at least a half hour motorway run every week and I dont think I have ever seen it smoke so i am guessing all is well. Other than the mpg and the clatter of a diesel all is well. :thumbs:
 

·
Registered
Joined
·
831 Posts
... the car knows when it needs done and looks for an opportunity, when the car is up to temperature and moving at a reasonable speed...
Riiiiight... it happened to me a few days ago at -17.5 degrees and 5 minutes after starting it up, in city traffic, at a stop light.
 

·
Registered
Joined
·
2,329 Posts
To avoid scorching the garage floor my local garage did a forced regen with a car (not mine) parked on the verge. That saved the garage floor but, as it was late August, the grass caught fire under the car. Luckily the apprentice was with the car and moved it but a big area of grass and hedge went up in flames.
 

·
Registered
Joined
·
1,961 Posts
I was with an AR technician and he did my readings. I went "Oh, its 75% clogged" and he said "no, being AR/Fiat it's the other way round and it's 25% clogged which is OK"
Just saying....!
 

·
Registered
Joined
·
41 Posts
Discussion Starter #14
Took the Italian Regen route and with a ploom of black smoke out the exhaust the regen took place. During that time the mpg was down to 18mpg and when foot taken of the gas the boost pressure drops straight to zero. Thanks for the info guys!
 
1 - 14 of 14 Posts
Top