Technical Twin EGR issues - 'EGR Cooler Syndrome' Symptoms but different Fault Codes - HELP!

[Dancingbear]

Hi all,

I’m hoping someone here might be able to shed some light on ongoing issues with my 2019 Fiat Ducato 35 Multijet II (250) ‘Sportivo’ twin-EGR, no AdBlue, currently on 84,000 miles.

Symptomatically they seem to mirror the EGR cooler syndrome that’s been well documented here, but none of the codes are the same: Over the last 8 months I’ve had the following fault codes:

March
P0683 – glow plug circuit - replaced
P0639 – throttle valve control - cleaned
P045E – EGR - HP replaced (in error)?

May
P045E – EGR - LP replaced

Aug
P041A – EGR temp sensor replaced

Spetember
P2002 – DPF efficiency below threshold (after failed motorway regeneration)

The first motorway journey after the Temp sensor was replaced, a DPF regen failed which initiated the P2002 code and EML.

Unfortunately these error codes have taken excessive times to be fixed and the van has been driven with the EML on – the Temp sensor code illuminated in the French Alps and we weren’t able to get it resolved until back in the UK – 1000 miles+… I now know the illuminated EML will prevent auto DPF regen .

Last week I had a mobile DPF specialist perform a diagnostic and clean at my home. The basics of his assessment were:

Parameter	Pre-Clean	Post-Clean
DPF soot load (%)	177	9
ΔP at idle (kPa)	0.4	0
ΔP at 2500 rpm (kPa)	2.2	0.7
Engine temp (°C)	80	94
MAF (mg/stroke)	448	386
EGR position (%)	0	0
EGT (°C)	628	184

He noted soot present in the tailpipe (which I noted 6 months ago) and suggests the DPF is probably damaged (based on soot and zero / low DPF pressures).

As a massive curve ball to this already complex picture, the DPF guy found my turbo electrically unplugged – which must be from previous garage work - Time scales unknown. Once reconnected, turbo faults cleared and it appears to boost normally again – both on the road and on the diagnostics.

At this stage, I think I know the following:

• This is going to be expensive!!!
• The DPF is almost certainly damaged and I have had soot in my exhaust for 6 months +
• The Turbo unplugged issue could be the root cause of this, as I imagine poor operation of the variable geometry in the turbo will make its operation ‘agricultural’ causing excessive soot! But it could also be only contributory or a complete red herring if it was only unplugged a few weeks with limited miles!???

So, I’m trying to avoid the usual “parts cannon” approach discussed on here and get to the cause rather than treating the symptoms.

I’ve purchased MultiECUScan - its in the post - so I can start logging and learning from the excellent posts many of you have already shared here. I’ve started reading through the twin-EGR and P0401/P0402 mega-thread, but because of the difference in presentation any different or targeted insight here would be hugely appreciated.

Before I dive in, some questions for you legends:

• Do these symptoms and readings suggest solely a cracked DPF or something else upstream (MAP / boost solenoid / EGR control, cooler etc etc.)?
• Would you DEFINITELY have to unplug the turbo to change LP or HP EGR or EGR Temp Sensor and therefore not plugged back in my my local garage?
• Whats the significance of the unplugged turbo?
• How would I be able to ‘prove’ that the garage left it unplugged?
• Any pointers on the next steps or first parameters I should log with MES to narrow this down?

I am not a mechanic of ANY sorts and have had a steep learning curve already – and I’m trying not to be driven into an early grave by this...

I’d really appreciate any informed thoughts or guidance on this!

Thanks in advance

 

[theoneandonly]

These 2 guides will be a lot easier to read than 60 or more pages

Twin EGR Problem

This does not refer to earlier single EGR systems or to later AdBlu SCR engines. Note this is a guide and not definative. It is up to you to make decissions. It is the result of my investigations of data from many contributors and discussion with...

www.fiatforum.com

Ducato twin EGR Engine with P0401 Code (2016 to 2019)

This does not refer to earlier single EGR systems or to later AdBlu SCR engines. Note this is a guide and not definative. It is up to you to make decissions. It is the result of my investigations of data from many contributors and discussion with...

www.fiatforum.com

Take screen shots of all current error messages and the freeze frame data for each)
Try this template
Start from cold and run for 20 mins if possible 10 mins at 60mph (motor way ideal)

No guess work from me until I've seen some data. Is it a 130 or 150? Many reasons for regens not occuring. @Fredastaire @bugsymike any idea about the unplugged turbo?

 

[theoneandonly]

 

[Dancingbear]

Amazing thankyou - Yes i've read both those guides but will need to do so a few more times to absorb the detail. I'm just about to go away working for a week or so, so it'll take me a few weeks to get the data but i will get onto it soonest!

I think my van is a 150 bhp, and hopefully i can come back with confirmation of the software version etc once ive got the MES up and running.

There should not be any fault codes at present because the DPF guy deleted them, and it completed the regen ok post wash despitre the low pressure etc.

The fault codes at the time of diagnosis / pre wash were:
P24A4-68 Soot load and Mileage with DPF lamp on
P2562-14 Variable Geometry Turbo Position Sensor - this cleared imediately when the connection was remade!

Very much appreciated!

 

[theoneandonly]

Thanks the P2562-14 Variable Geometry Turbo Position Sensor imedeately says 150 or 180, the 130 doesnt have a VVT Variable Vane Turbo.