407 Hdi 2.7 DPF tank and Eolys union plug

[407]

Thanks Richard

I'll check the pressures (and empty the tank - will try and find out what was added)

So if Eolys is injected on each diesel tank fill up, and the additive tank takes 3 litres which lasts say 140,000 kms, it seems the squirt on Eolys on each tank fill up is around 10.7 ml ?

eg ( 3000 ml / 140,000 kms ) * 500 kms per tank full (average) = 10.7 ml

Ignoring resetting the warning bells and noting Marc says parts no longer available, is injecting 10 ml syringe of Eolys into the diesel tank on each fill up a temp work around ?

[407]

Contents of the Eolys tank - all up around 4 litres (2 litre bottle on the left and 3 litre on the right)

Seems the clear mixture has a green tinge which is denser / heavier than the brown liquid, which I assume was the original remaining Eolys

The clear mixture also leaves a yellow stain (see ice cream container). It does not smell like diesel and diesel would not leave a yellow stain.

Any guesses as to what it might be ? Could it be one of the other DPF fluids put in by mistake ?

regards

[wheeler]

Oh dear, looks like Kiwi flavour Mad Dog

[GiveMeABreak]

I dread to hazard a guess, but whatever it is you won't want any of that injected into your fuel tank.

Whether this has affected the pump operation previously I don't know, but even mixing the wrong Eolys additive can cause pump failure.

[407]

Finally pulled the additive tank out and tested the pump.

Not pumping so suspect it is a goner - I 've read it is a solenoid dosing pump (eg 1 pulse is say 1 ml so when the tank flap opens the ECU pumps it a few times to release the 10 ml or so of Eolys into the tank)

There is also a rattle inside so suspect something is loose.

Tank unit is sealed so i might cut it open for a look see - I suspect you might be able to jerry rig a pump from a CITROEN C4 Picasso Additive Tank Pump 9658411580 1525lk

I've found a spare unit so will see if that works and fixes the issues (or will just add a syringe of 10ml of Eolys per tank fill up as a bypass)

Some info of interest

Tech specs of Eolys 176 - https://www.catflex.net/images/media/in ... YS_176.pdf

CAS numbers 90622-58-5;753480-32-9 Diesel additive

Basically not toxic unless you drink it

Made up of 75% hydrocarbons (alkanes 90622-58 (to mix with diesel I guess) and 25% cerium (a metal, 58 on the periodic table) and iron oxide 753480-32-9 (combined they lower the ignition point to < 200 degrees)

As an aside, iron oxide mixed with aluminium makes thermite, which sort of explains how it lowers the DPF regeneration ignition temp

I suspect the clear liquid added was a DEF fluid / Ad Blue ( injected into the exhaust to lower nitrogen oxides), which is a mix of urea (32.5%) and water (67.5%) (which is also explains why the Eolys floats on top)

The yellow stain is just iron oxide

Also Bosch manual (at http://citroeny.cz/navody/c5/System_Bos ... cky%20.pdf) within 100km of the DPF risk of blocking warning, drive for minimum of 3 mins at speed greater that 50 kms to generate exhaust temp (and exhaust pressure to blow the burnt ash out) to start DPF regeneration

[wheeler]

Soak some of the clear liquid on a rag & leave is for a few days, if it's adblue it will start to crystallise.

[407]

Some updates

a) decided to test if the car would run and also regenerate without the additive tank connected. So, bolted the diesel tank back up, plugged the tube to the tank and mixed around 10 mm of Eolys with diesel and poured into the tank (mine was just filled up). Took it for a high speed run (80-90 kms) in 3rd gear and after around 15 mins the "risk of blockage" warnings stopped coming up. Also the MIL light cleared it self. Seems the car does not care if the tank is there or not, given there is only one electrical connection to the pump.

My theory is the Eolys gets burned with the diesel and the cerium / iron oxide is "soaked" up in the ashes in the DPF - when it gets hot enough (eg high speed runs or 450 degrees), it triggers a burn (think thermite reaction) and clean / unblocks the DPF.

b) I cut an opening into the DPF tank (sharp stanley knife worked) to see what was inside

Surprise, surprise the two wires to the pump where loose - I suspect the Ad blue water and the connectors did not like each other. The loose rattle was the electrical plastic plug that came loose.

I unclipped and removed / cleaned the pump with contact spray and after a few hits / air compressor blows, could get it to pump - its a pulse type will only pump once for every touch to the battery. Again, I suspect it did not like the Ad Blue water as there was a bit of rust.

The plan is to fix the electrical, refit and reweld the tank top and see if it works.

Fall back plan is top up the tank each refill with Eolys - nice

See happy snaps

[407]

So 3 weeks later and around 400 kms later, no DPF blocking warnings to date and seem to have lost the black smoke (maybe it was the DPF cleaning itself as I also had a bit of smoke coming out from under the hood once in a while, which is probably the DPF heating to 450 degrees). Car seems to be driving okay

Checked with Diag and get the following report on SID201 Particle emission Filter parameters

Differential pressure 0 at 672rpm 256 millibars at 3488 rpm

Distance since last regen 25 kms (sound about right as I had some smoke coming out under the bonnet)

Particle filter load 12% ( I assume this is the current amount of unburnt particles before a regen)

Particle filter clogging level 54% (I assume this is the burnt particle ash so when this gets to say 80% the DPF needs a wash)

Status OK

Some weeks ago I had some strange readings / ODB codes on the rear air flow meter and so put a new one in.

P0104 (intermittent) rpm 1824 rear 16 kg/H , front 180 Kg/h

P010F (intermittent) rpm 1920 rear 20 kg/H , front 200 Kg/h

P0102 (permanent) rpm 0

I also ran Diag SID201 air circuit information and got the following

At 672rpm at 2016 rpm at 3100 rpm

Airflow 1 (rear) 343 240 545 mg/impulse (could this be related to DPF / EGR / pipe blockage issue ? )

Airflow 2 (front) 501 332 741

Air flow setting 507 300 638

Measured air flow 420 294 627

The new air flow meter still reads the as the old one so I swapped the two units and the reading did not change, so assume all three air flow meters are all okay.

Given the lower readings on the rear air flow meter, does this suggest the rear air flow (eg EGR) is somehow blocked at low speeds but seems to get better at higher speeds ?

Also have some inconsistent readings on SID201 Fuel circuit information re injectors (flow correction)

At 672rpm at 3232 rpm

Injector 1 88 % 100% (front ?)

Injector 2 90 % 100% (front ?)

Injector 3 82 % 100% (front ?)

Injector 4 110 % 100%

Injector 5 115 % 100%

Injector 6 113 % 100%

I assume 1, 2, 3 are the front bank injectors. There is a side message that says a fault is raised if the value reaches 60% or 140% - what does this message mean ?

Finally, for fun, I pulled the Eolys additive solenoid pump apart. Seems the water did it no good as seized up the internal sliding plungers etc - a bit of fine grit sandpaper and it seems to be working again (eg clicking and moving the various components to suck and pump the oil).