Regen

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Steve Walsh
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Regen

Post by Steve Walsh »

Does anyone know what the engine/vehicle speeds trigger the regeneration of the particle filter, and how can you tell when it is happening

Citroen C5X7 Tourer 2.0 hdi 2013.
VF7**************[VIN obfuscated, can be read by forum staff]


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GiveMeABreak
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Re: Regen

Post by GiveMeABreak »

It is nothing to do with the actual vehicle speed that determines regeneration Steve.

It is quite a complex process of evaluation to determine when regeneration needs to occur based on engine temperature, driving conditions, estimated soot loading percentage, distance since last regeneration and other factors as well as whether the last attempts to regenerate the filter were successful or not.

Normally this takes place when driving under the right conditions, so you won't notice it - as sometimes assisted regeneration is not needed if the exhaust gas temperature is hot enough (circa 550°C) to naturally regenerate.

Main information used for monitoring the particle filter:
  • Calculation of the weight of soot present in the particle filter
  • Differential pressure (Measurement)
  • Exhaust gas temperature
  • Inlet air flow
  • Information on mixture coming from the oxygen sensor
The first 2 items are dependent on the soot loading in the particle filter.
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Steve Walsh
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Re: Regen

Post by Steve Walsh »

Thanks Marc

I have only done very short runs for a couple of months, I must give it a long one to give it a clear out

Steve
RichardW
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Re: Regen

Post by RichardW »

One of my 1.6 16Vs used to run slightly rough when regenning, the other no sign - the current 2 there's no change at all. The only other sign if the conditions were right was the HRW coming on. I would just keep driving it if / till the light comes on - there's no point going on a run for the sake of it, it won't regen just because you are on a run unless it's due. So you could do 50 miles, and be just 3 away from a regen. If the warning comes on, take it for a 10 mile or so open road drive, no need to hammer it, normal driving is plenty.
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Steve Walsh
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Re: Regen

Post by Steve Walsh »

Thanks Richard

Steve