Technical ECU problems !

[Jayen4]

O.K. Guys..... I have an ongoing problem with the ECU on my Doblo 1.9 120 .

The history is : The ecu was re-programmed (twice) a while back (because the 'technician' - hah ! didn't do it right the first time . This was because it had had the dpf deleted , and presumably had the ecu remapped to suit.....When it came to MoT time the tester ( who had tested the car twice before , with the 'deleted' dpf in place) decided that he didn't like seeing the deleted dpf and I had to buy a new dpf and hence reprogramme the ecu back to 'standard' !
Now , coming up to date : I have had my local mechanic gut the dpf again ( this time with no outward signs ) and he had real problems re-mapping the ECU again..... He thinks that the ECU has been 'corrupted' somehow.... So the ECU was sent of to Veizu Technologies in the midlands and was again re-programmed to take account of the dpf delete and a EGR delete .
It has now developed a fault where after running for a while , the engine will start 'hunting' and throwing a LOT of white smoke out ...... We think that it is trying to do a regen , when there is no regen anymore and my mechanic thinks that the old programming is trying to reassert itself , hence throwing up these faults ! When it does this , if the engine is switched off and restarted , it seems to reset something and runs normally for a certain time , before it does it again !
He has suggested getting a replacement 'matching' ECU that can be properly programmed to my car..... Apparently , certain numbers on the current ECU have to be the same as any replacement ??
Does anyone have any insight into this problem ,please and can help me get this sorted once and for all !!?? ..... Maybe someone has a suitable ECU for sale ? .... We think that the original ECU is so screwed up as to not be able to take a re-program properly ! ...... I need help !!

 

[bugsymike]

Don't know if relevant but I had a basic 105hp 1.9 JTD Doblo 2005 which only used a "particle filter " not a DPF with pipes and pressure sensors etc.
So would an earlier ECU pre DPF be one direction to try once matched to your vehicle or are all the 120hp versions using DPF regardless of age.
Perhaps a good ECU specialist can advise.
What codes are being read by diagnostic tools?

 

[Jayen4]

Don't know if relevant but I had a basic 105hp 1.9 JTD Doblo 2005 which only used a "particle filter " not a DPF with pipes and pressure sensors etc.
So would an earlier ECU pre DPF be one direction to try once matched to your vehicle or are all the 120hp versions using DPF regardless of age.
Perhaps a good ECU specialist can advise.
What codes are being read by diagnostic tools?

Hi Bugsy... My particular car has (had ) a DPF fitted . Don't know about any varieties . As I said , it's already been re programmed by Veizu but is clearly not right ! Don't know what codes might have been thrown up as my mechanic has been doing the actual work .
I have found a replacement ECU on eek bay , with matching part numbers , but it's rather expensive ( £80 ! ) , but if that's going to fix the issue once and for all , then I suppose that I'll have to go for it ....

 

[bugsymike]

Hi Bugsy... My particular car has (had ) a DPF fitted . Don't know about any varieties . As I said , it's already been re programmed by Veizu but is clearly not right ! Don't know what codes might have been thrown up as my mechanic has been doing the actual work .
I have found a replacement ECU on eek bay , with matching part numbers , but it's rather expensive ( £80 ! ) , but if that's going to fix the issue once and for all , then I suppose that I'll have to go for it ....

No guarantee that that will be the answer and can cause problems with immobiliser and BCM etc. if applicable.
In the past with older cars it was possible to change the ECU , immobiliser side and chipped keys to sort the problem but a lot more specialised these days.
I would like to see the error codes read fully by a good diagnostic tool before throwing money at it.

 

[Quantum Tuning]

Possible Causes of Your Issue:​

1. Corrupt or Incomplete Remap:
   • If the ECU wasn’t fully or properly flashed, remnants of the old programming (especially the regen function) might still be active.
2. Incorrect DPF/EGR Delete Mapping:
   • Some ECUs require specific modifications beyond just disabling DPF-related functions. If not done correctly, the ECU may still attempt to regenerate, leading to excessive white smoke and erratic behavior.
3. ECU Software Lock or Corruption:
   • Some ECUs have a form of "write protection" that can interfere with proper programming, preventing a clean remap from taking hold.
4. Hardware Issue with the ECU:
   • If the ECU has been flashed multiple times incorrectly, it may have developed hardware faults or software corruption, making further programming unreliable.

Solutions to Consider:​

1. Find a Correctly Programmed ECU Replacement
   • Yes, you will need an ECU with matching part numbers (usually found on the ECU sticker).
   • Ensure it's "virginized" (reset to factory state) so it can be coded to your vehicle.
2. Full ECU Reset & Fresh Remap
   • Some specialists can fully reset the ECU and perform a fresh remap using original firmware before modifying it again.
3. Check for Stored Fault Codes
   • If your mechanic hasn’t already, scanning for error codes (not just clearing them) might provide clues about what's still active in the ECU.
4. Use a More Experienced ECU Tuner
   • A specialist with experience in Fiat/Alfa/Multijet ECUs may be able to sort it without needing a full replacement.

Finding a Replacement ECU​

• Search online (eBay, specialist breakers, Fiat forums) for a matching ECU.
• Some ECU companies offer cloned units that are pre-programmed to your car's settings.