what happens if I do not replenish Eolys fluid?

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johnhuson
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what happens if I do not replenish Eolys fluid?

Post by johnhuson »

C5 2002 2.2 Auto estate. Will the car sensors warn me of a low level? Does my earlier Mk1 have the FAP with float tank so if
I do top up with a litre it automatically re calculates the level or does the tank need reprogramming with Lexia? (I have one if you need it).

If I ignore all warnings and do not top up the Eolys fluid tank what happens? The tank currently tells the Lexia there is 1gm left but
no dashboard warnings are evident. Am not sure the 1gm is one gram fluid left?

Thank you. John.

Does 'Anders' still contribute to this forum? I used to benefit from his wise words going back to BX and Xantia times.
Last edited by johnhuson on 04 Apr 2019, 12:30, edited 1 time in total.

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Paul-R
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Re: what happens if I do not replenish Eolys fluid?

Post by Paul-R »

Yes, the 2.2 does have a FAP. I'm sure that Marc, or of the others with access to official documentation will be able to give chapter and verse on this but this is what I know/remember/guess.

If the Eolys runs out then for a short while nothing untoward will happen as the FAP fills up with particulates. The problem will come when regeneration is initiated. The Eolys is there to reduce the temperature at which regeneration can take place so the probability is that the particulates will not burn off. This means that in very short order the FAP will become blocked and the engine just won't work as the exhaust gasses can't get through properly.

There will probably be lots of warning lights and messages on the dash whilst all this is happening so you won't be unaware of it! AFAIK none of the Eolys measurements are real, they're all worked out by the ECU (or BSI if the car doesn't have an ECU) so it's theoretical. You may have 20g, or more, actually left which means that you might be able to continue for much longer than if it were really empty. But bear in mind that if there is warning light illuminated that the car will not pass the MOT so you will come to a halt one way or another.

When you top-up the Eolys (early cars) or replace the Eolys pouch (all later cars) you have to use Diagbox/Lexia to record that fact. I have read that some of the very early 2.2 HDi cars (could be yours?) have an ECU that can't be reset and has to be replaced.

Finally, there are several different types of Eolys, some of which replace earlier types of Eolys and others which must NOT be used as a replacement. Your VIN will be needed to find that out and if you post it up the forum software will mask it. I would post it up as soon as possible if I were you.

Others will know better than I but I think that Anders does not post as much nowadays.

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GiveMeABreak
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Re: what happens if I do not replenish Eolys fluid?

Post by GiveMeABreak »

You will very likely have a Diesel Particulate Filter and therefore an additive tank on this engine, but VIN is needed to confirm, so post it up here.

Assuming you do, then yes, you will get a warning concerning the additive level being low.

Let's clear up your assumptions about the tank. The Eolys additive tank does NOT have a float level. The fuel injection ECU (or as this is an earlier model may have a separate additive ECU) estimates the level remaining based on original quantity of additive, the miles driven and quantity of additive injected to date.

You need to ensure the correct additive is used and yes, you will need to reset additive counter on either the injection ECU or the additive ECU after adding Eolys. It is always better to top it up rather than just adding a litre here and there as the tank should be filled when you reset it so that the system knows the tank is full. If not, the system will not know the additive tanks is full.

If, when the additive level is estimated to be low you ignore the warning, then eventually the ECU will put the vehicle into a backup mode and will reduce engine power available until the system is topped up and reset. You may get up to a 1000 miles and that will be it before reduced power mode kicks in.

On the later systems, the engine ECU estimates the remaining additive fluid against when the next service interval is due. If it estimates there is enough additive until your next service, the light is not lit until later, but if it estimates there is not enough fluid left until the next service, the low level warning is put up earlier.

Yes, Lexia is used to reset the additive ECU or the Injection ECU depending on system. However,. it has been noted that on earlier models with additive ECUs, they can be problematic resetting them and have required a new additive ECU where they will not reset.

johnhuson
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Re: what happens if I do not replenish Eolys fluid?

Post by johnhuson »

Thanks to you both; Marc and Paul-R for being so informative, it is much appreciated.
VIN: VF7**************[VIN obfuscated, can be read by forum staff].

Knowing which type of fluid and what system it is will be helpful. I purchased a spare ECU some time ago and they both read the same
on my car.


John.

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Re: what happens if I do not replenish Eolys fluid?

Post by johnhuson »

For information: The Lexia confirms it has regenerated recently.

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GiveMeABreak
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Re: what happens if I do not replenish Eolys fluid?

Post by GiveMeABreak »

Ok, so your system, being first generation, uses Eolys DPX42 and should have a white click fit union on the additive tank.

Your additive is specific and so you cannot use Eolys 176, Infineum F7995 or Eolys Powerflex you must use Eolys DPX42.

Walker provide both the original Eolys DPX42 or their own cheaper equivalent brand.
Eolys DPX42Eolys DPX42Walker AlternativeWalker Alternative
1 litre 4,5 litres1 litre4,5 litres
80600805008061480615
So here are the Walker product numbers for both Eolys DPX42 and their equivalent Walker Alternative for each quantity.

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myglaren
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Re: what happens if I do not replenish Eolys fluid?

Post by myglaren »

If you mean AndersDK then he hasn't logged in since Nov 2014.

Shame as he is very knowledgable and a very pleasant chap.

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Re: what happens if I do not replenish Eolys fluid?

Post by crapday69 »

Paul-R wrote:
04 Apr 2019, 11:50
But bear in mind that if there is warning light illuminated that the car will not pass the MOT so you will come to a halt one way or another.


I am sure this is only for post 2007 diesels so any pre 07 diesels will not fail an MOT with the EML illuminated.

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GiveMeABreak
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Re: what happens if I do not replenish Eolys fluid?

Post by GiveMeABreak »

From the current MOT inspection manual:
Engine malfunction indicator lamp
Turn on the ignition and check that the engine malfunction indicator lamp (MIL) illuminates and then goes off. On some vehicles it will be necessary to start the engine before the MIL goes off.

You need to inspect MIL fitted to diesel vehicles with 4 or more wheels and first used on or after 1 July 2008.

detheridge
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Re: what happens if I do not replenish Eolys fluid?

Post by detheridge »

Hi folks,
I've had the Fap warning message flash up this morning after filling the car up. It went out after a few seconds and the sun was in my eyes so I couldn't read the full message.
How long can I run the car for before it goes into recovery mode?
Does this mean I need to get the fluid topped up or a new dpf? (Mileage 173k, but what service history there is doesn't say if the dpf has been replaced or when).
Which fluid is best for my car? (2007 2.2HDI auto, VIN is VF7**************[VIN obfuscated, can be read by forum staff].
Does the fluid need to be replaced before or after regen (a local guy does regeneration for a quoted £45 )

David.

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GiveMeABreak
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Re: what happens if I do not replenish Eolys fluid?

Post by GiveMeABreak »

Your Build Number is 11118. So you need Eolys 176.

Walker do an equivalent 1 litre kit (Part 80601), or a 3Lt kit (80501)

You don't need to do any regeneration at a garage - your car regenerates the particle filter as necessary as you are driving without you doing anything. A forced regeneration is not recommended unless really necessary due to the toll it places on system components and the extreme heat generated from the engine.
  • As for how long you have.... the additive quantity in the additive tank is not physically measured. It is estimated based on when it was filled against the amount it has injected into the tank over time based on fuel added and some other factors. The older system may just flag up when it thinks it needs topping up - the newer systems work out the next service interval due against the amount of additive it thinks is in the tank and if it thinks there will not be enough before the next service is due it will flag up the low fluid warning. You'll only get a limited amount of time 500-1000 miles maybe before it will drop the engine into backup reduced power mode.
  • We can't ascertain when or if the DPF has been replaced.
  • The Engine ECU will have to be reset when the fluid is topped up. You will need a Lexia or somebody with a Lexia kit to do this.
Click Fit ColourRPODateEOLYS
WhiteTo 9492To 04/11/2002EOLYS DPX42
GREEN9493 to 1210905/11/2002 to 03/01/2010EOLYS 176
GREEN12110 to 1216504/01/2010 to 28/02/2010Infineum F7995
BLUE12166 on01/03/2010 onEOLYS Powerflex
Click Image to Zoom
Walker.PNG

detheridge
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Re: what happens if I do not replenish Eolys fluid?

Post by detheridge »

Marc,
many thanks as ever for your comprehensive info. I've booked my car in for an Eolys refill next Tuesday so I won't be going many miles over the weekend, and I can happily forget the forced regeneration.
How many litres do you think I might need for this? 3 or more, or less?
One point of clarity: are the regeneration additives something I'll need as well? I've never come across them before.
Best wishes,
David.

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GiveMeABreak
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Re: what happens if I do not replenish Eolys fluid?

Post by GiveMeABreak »

Hi David - I would get a 3 litre pack as the car's ECU obviously thinks it is low. The 1lt kits are generally for interim top ups. Not sure I understand your next question
- the Eolys 176 (or the Walker equivalent) is the actual additive. You don't need anything else. :-D

detheridge
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Re: what happens if I do not replenish Eolys fluid?

Post by detheridge »

Well, the garage has refilled the Eolys tank with 3 litres, reset the code (twice) and the damn thing is STILL telling me that the level is low. Any ideas folks?

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Re: what happens if I do not replenish Eolys fluid?

Post by Harlequin »

I have had both a mk1 (2002) and a mk1 r (2007) 2.2 HDi.

The car has EOLYS and a DPF (Diesel Particulate Filter) or FAP to the French. The EOLYS works in 2 ways, it acts as a flocking agent and helps lower the combustion temperature of the larger particulate matter inside the DPF itself , when a regeneration is performed.

The earlier 136bhp 2.2 HDi will use DPX42 EOLYS , and the later use DPX176 - although PATFLUID can be used for both.

However the challenge with the mk1 (early) , is actually resetting the system. I had to replace the £100 cable between the fuel filler cap and the eoyls injector before the system was happy enough to reset the ECU - and I had to replace the ECU as well (its in the offside passenger door sill)