Soot On 1.6 Hdi Engine

[KeithC5]

I have soot on the right hand side top of my 1.6HDi engine, the car runs fine apart from the occasional puff of black smoke from the exhaust and the appearance of the FAP warning light every few weeks, which I drive with some revs on and the service light soon goes off, the FAP filter was changed about 4000 miles ago. Has anyone else seen this, what causes it and how do I cure it?

 

Thanks

[coastline taxis]

I have soot on the right hand side top of my 1.6HDi engine, the car runs fine apart from the occasional puff of black smoke from the exhaust and the appearance of the FAP warning light every few weeks, which I drive with some revs on and the service light soon goes off, the FAP filter was changed about 4000 miles ago. Has anyone else seen this, what causes it and how do I cure it?

 

Thanks

Not to sure without having a look but id be going down the following routes and checking the following for leaks.

Exhaust manifold and flexi and clamps.

egr valve and all pipes.

turbo and pipes.

just take a good look round the engine as it sounds like a leak on the exhaust side

 

As for your fap warning light get your car on the motorway cant remember the speed its either 50 or 70mph. keep it in 4th and do 10 to 15 miles youll see the crap come out the back and that should sort that out. but check the speed and distance if you can as i know they arnt citroens advice but they are what we do and they do work.

All diesels need a good run every now and again as there a dirty enginge and get clogged up with little stop start journeys round the town

[davidad]

On an Hdi with FAP you should NEVER see any black smoke or crap from the exhaust. If there is then there is something wrong with the FAP.

[coastline taxis]

On an Hdi with FAP you should NEVER see any black smoke or crap from the exhaust. If there is then there is something wrong with the FAP.

been down this road a thoushand times read earlier post regarding fap then do what was said earlier and itl be ok

[davidad]

been down this road a thoushand times read earlier post regarding fap then do what was said earlier and itl be ok

But you still don't seem to understand what the FAP does or how it works! The whole point of the FAP is that it traps all the soot particles which cause the black smoke emitted from a conventional non-FAP diesel. When the ECU senses that the filter is getting clogged it puts the engine into regeneration mode which increases the exhaust gas temperature to a point where the soot burns and is converted to ash. All this happens inside the filter so there is never any black smoke from the exhaust. Eventually the filter becomes clogged with ash and has to be replaced.

 

Under normal driving conditions all this happens without the driver ever being aware of it. In certain driving conditions (e.g. moving slowly in heavy traffic, stationary with the engine idling for a long period, lots of short journeys) there is a risk of the filter clogging because under those conditions the ECU is unable to put the engine into regeneration mode. When this happens the "Risk of particulate filter clogging" message will appear on the dashboard display or whatever on your particular model. The solution is to drive the car as soon as possible at a steady speed of more than 40mph for at least 5 minutes which will allow the regeneration to take place and unclog the filter. This is not the same as the usual advice for a non-FAP diesel which is to drive the engine at high revs to blast out all the crap.

 

To go back to the original post, if the FAP filter was changed only 4000 miles ago and the car is not just used for short journeys or constantly in heavy traffic then it should not be displaying warning messages. Nor should it EVER give out any black smoke. I would take it back to whoever changed the filter and get it checked out.

 

I presume the eloys fluid was replenished at the same time as the filter was changed?

[coastline taxis]

But you still don't seem to understand what the FAP does or how it works! The whole point of the FAP is that it traps all the soot particles which cause the black smoke emitted from a conventional non-FAP diesel. When the ECU senses that the filter is getting clogged it puts the engine into regeneration mode which increases the exhaust gas temperature to a point where the soot burns and is converted to ash. All this happens inside the filter so there is never any black smoke from the exhaust. Eventually the filter becomes clogged with ash and has to be replaced.

 

Under normal driving conditions all this happens without the driver ever being aware of it. In certain driving conditions (e.g. moving slowly in heavy traffic, stationary with the engine idling for a long period, lots of short journeys) there is a risk of the filter clogging because under those conditions the ECU is unable to put the engine into regeneration mode. When this happens the "Risk of particulate filter clogging" message will appear on the dashboard display or whatever on your particular model. The solution is to drive the car as soon as possible at a steady speed of more than 40mph for at least 5 minutes which will allow the regeneration to take place and unclog the filter. This is not the same as the usual advice for a non-FAP diesel which is to drive the engine at high revs to blast out all the crap.

 

To go back to the original post, if the FAP filter was changed only 4000 miles ago and the car is not just used for short journeys or constantly in heavy traffic then it should not be displaying warning messages. Nor should it EVER give out any black smoke. I would take it back to whoever changed the filter and get it checked out.

 

I presume the eloys fluid was replenished at the same time as the filter was changed?

so why then do the dealers charge people for taking the vehicle out onto a motorway and giving it a hard drive. like i say this topic has been talked about on hear a few times go back through the search facility and have a read of them

[davidad]

so why then do the dealers charge people for taking the vehicle out onto a motorway and giving it a hard drive. like i say this topic has been talked about on hear a few times go back through the search facility and have a read of them

They don't on cars with FAP. What a mechanic can do if the filter is clogged is to perform a forced regeneration which is done in the workshop, not on the road.

[coastline taxis]

They don't on cars with FAP. What a mechanic can do if the filter is clogged is to perform a forced regeneration which is done in the workshop, not on the road.

Ok here we go

The particle filter is a stand alone unit and placed before the cat in the exhaust system. Its job is to remove soot from the exhaust gasses.the cat then gets on with its own job of converting co into co2 and the cat does not need the fap filter to operate.

Diesel are much better than petrols and release less co2 but in return diesel fumes are black and full of soot and this is what the fap filter tries to combat

 

Most fap systems require a fuel adative to be mixed in with the fuel and is done automaticly when fuel is put in the tank the car registers the amount of diesel added and adds the right amount of aditive to the tank. The adative is stored in its own tank and and needs replacing when run down roughly every 50 to 70 k the adative made by rhodia inc formaly rhone poulenc and sold under the brand name of eolys and its job is to lower the point at wich carbon will burn and clear the soot out of the filter it is called regeneration

 

The regeneration is started when pressure sensor either side of the fap filter notice a diference due to the filter being clogged or part clogged then this is what happens

the heater plugs are turned on and extra fuel is injected into the engine to create so much heat that it literelly just burns the soot away

This can be done with the right diagnostic tools and as well as doing the above the engine goes to 4500 revs and stays there for 40 mins to burn the soot off this id called forced regeneration

 

You can also do this yourself by getting your car onto the motorway keeping it at 70mph in 4th gear for 10 mins must be 10 mins or youl have to start the process over again

 

personaly i cant see the point of the system as what it stops from going out the exhaust is out weighed by the toxins (carconogenic i belive) it produces itself.

and that my friend is that

[KeithC5]

Not to sure without having a look but id be going down the following routes and checking the following for leaks.

Exhaust manifold and flexi and clamps.

egr valve and all pipes.

turbo and pipes.

just take a good look round the engine as it sounds like a leak on the exhaust side

 

As for your fap warning light get your car on the motorway cant remember the speed its either 50 or 70mph. keep it in 4th and do 10 to 15 miles youll see the crap come out the back and that should sort that out. but check the speed and distance if you can as i know they arnt citroens advice but they are what we do and they do work.

All diesels need a good run every now and again as there a dirty enginge and get clogged up with little stop start journeys round the town

 

Thanks for the reply, can you advise where the EGR valve is, I have also thought about the valve on the inlet side but don't know where that is either. Are they accessible and easy to change, can they be checked without a dealer having to hook them up to a computer?

 

Thanks again

[coastline taxis]

Thanks for the reply, can you advise where the EGR valve is, I have also thought about the valve on the inlet side but don't know where that is either. Are they accessible and easy to change, can they be checked without a dealer having to hook them up to a computer?

 

Thanks again

HELLO

I wouldnt bother to much about the inlet side because if it soot that your seeing then that indicates burnt fuel so itl be on the exhaust side