C4 picasso 2017 intermittent judder in random gears

[sofnet2000]

Hello folks, I have had this issue with 2017 c4 picasso flair egs , 40k on clock, it has happened to me 3 or 4 times, out of the blue the car judders in 3rd, 4th, 5th gear without warning, no codes even with diagbox, on all occasions judder stopped after few minutes. Changing to manual did not make difference even in neutral car was juddering and shaking.

Any ideas at all?

[PaulC5]

Is the servicing up to date including replacing the fuel filter ?

I had some judder on our C5 on the A1 which cleared after a couple of miles. Checking live data showed the MAP sensor values were not changing much and on removal it was blocked. I cleaned it with carb cleaner which helped except some codes were then given but acceleration was a lot quicker. I had to replace it in the end. I also replaced the fuel filter but cutting up the old one found it was clean and there was no sign of any water in the fuel. The fault has not happened since and I do not know if the replacements helped but it still accelerates quicker and now on accelerating it can rattle a bit. I previously had a few messages of boost pressure less than expected which may have been the MAP sensor. I also replaced the MAF but I think that was not needed but I thought it may have been faulty since with the engine not running it gave a low value of about 4 and the new one also did this.

[sofnet2000]

it did happen to me few more times again, one of them between 2nd and 3rd gear, any ideas? does this mean the gearbox has had it? how can gearbox just go like that at 40k?

[sofnet2000]

It's unlikely to be the gearbox (remember this is not an automatic)!

It may be that the clutch biting point needs resetting using the diagnostic tool. I'd get the dealer to look at it and run a diagnostic on it, as the system can be quite complex and some independents may not know what they're doing.

Still waiting for the dealers appointment, they are very busy
I had it again today and it was worse, the car started shaking whilst at traffic light and then the engine cut off and battery sign showed up, I managed to get it back home and run a diagbox diagnosis on it, this time few codes appeared mostly about gearbox and communication with LIN, file attached

[GiveMeABreak]

You image is only showing one code at the bottom of the first page. I've deleted the image with your VIN and other details for your security, so please just provide the 7 digit fault codes like the U1310 86, that's all I need. I have the VIN from the picture.

[GiveMeABreak]

Now I have your VIN there has been some misunderstanding from your first post - you don't have a piloted manual EGS gearbox! You have an AT6 fully automatic gearbox. So ignore everything that I have mentioned - I have now deleted those posts as they are not relevant to this gearbox.

Just post up the codes and we'll see what we have.

[sofnet2000]

Now I have your VIN there has been some misunderstanding from your first post - you don't have a piloted manual EGS gearbox! You have an AT6 fully automatic gearbox. So ignore everything that I have mentioned - I have now deleted those posts as they are not relevant to this gearbox.

Just post up the codes and we'll see what we have.

Here are the codes attached plus the report, it can be seen that since the shaking started there were no codes for the gearbox, first time they appeared is yesterday.
There are other codes e.g parking sensors and boot but both these are working fine including park assist.
The known fault are drivers side mirror no folding back, driver's side keyless access intermittent sometimes works and sometimes doesn't and also the auto wiper it doesn't work since some idiot at big motoring world where I bought it from back in Dec 22 tried to fix auto dusk sensor and started downloading stuff to the ECU as he said and then ended up changing the sensor which fixed the light but not the wipers.

report : https://www.dropbox.com/scl/fi/w5izhgth ... c5ktk&dl=0

pictures below

[GiveMeABreak]

Ok, so with this new information, I'm not going to go any further as I think the idiot who tried to configure your BSI has basically screwed it up and doesn't know what he's doing. If he's changed settings that are not supposed to be changed or left the BSI in an unconfigured state, then it can cause a myriad of problems.

There are too many faults here for me to realistically look at and I think many will be caused by the person who doesn't know what he's doing at the place you bought it from.

If you have warranty, take it back as not fit for purpose or get them to foot the diagnostics bill from Citroen to have it programmed correctly.

If no warranty, you may have to bite the bullet, take it to Citroen and pay for a diagnostic £120 inc. VAT per hour and advise them that the idiot sales man has probably mucked up the configuration. Citroen should be able to download and check the BSI configuration from their servers and ensure it is correct. Then you may be in a better position to determine what are real faults and which ones may have been caused by his incompetence.

[sofnet2000]

Ok, so with this new information, I'm not going to go any further as I think the idiot who tried to configure your BSI has basically screwed it up and doesn't know what he's doing. If he's changed settings that are not supposed to be changed or left the BSI in an unconfigured state, then it can cause a myriad of problems.

There are too many faults here for me to realistically look at and I think many will be caused by the person who doesn't know what he's doing at the place you bought it from.

If you have warranty, take it back as not fit for purpose or get them to foot the diagnostics bill from Citroen to have it programmed correctly.

If no warranty, you may have to bite the bullet, take it to Citroen and pay for a diagnostic £120 inc. VAT per hour and advise them that the idiot sales man has probably mucked up the configuration. Citroen should be able to download and check the BSI configuration from their servers and ensure it is correct. Then you may be in a better position to determine what are real faults and which ones may have been caused by his incompetence.

When I took it there they said he was citroen expert tho lol, unfortunately it isn't under warranty

What I do not understand how come the issues did not show up all this time nearly a year since he mucked about, you can see it in the full report where all the data became 0 since 52k km (31k miles)?

Citroen will charge £120 an hour? so this could end up costing a fortune? I phoned them an the earliest appointment was october, can this be done somewhere else?

[sofnet2000]

Ok, so with this new information, I'm not going to go any further as I think the idiot who tried to configure your BSI has basically screwed it up and doesn't know what he's doing. If he's changed settings that are not supposed to be changed or left the BSI in an unconfigured state, then it can cause a myriad of problems.

There are too many faults here for me to realistically look at and I think many will be caused by the person who doesn't know what he's doing at the place you bought it from.

If you have warranty, take it back as not fit for purpose or get them to foot the diagnostics bill from Citroen to have it programmed correctly.

If no warranty, you may have to bite the bullet, take it to Citroen and pay for a diagnostic £120 inc. VAT per hour and advise them that the idiot sales man has probably mucked up the configuration. Citroen should be able to download and check the BSI configuration from their servers and ensure it is correct. Then you may be in a better position to determine what are real faults and which ones may have been caused by his incompetence.

I took it to Citroen and was told they cannot find anything wrong with it, and it doesn't even need an update, the software is all good!! I am puzzled !!!

[GiveMeABreak]

That's not the same as what I'm suggesting.

They may be looking to see if the physical BSI has a software update outstanding - which it may not. That is different to asking them to check that the BSI is actually configured correctly as a result of whatever the other bloke did to it.

[sofnet2000]

That's not the same as what I'm suggesting.

They may be looking to see if the physical BSI has a software update outstanding - which it may not. That is different to asking them to check that the BSI is actually configured correctly as a result of whatever the other bloke did to it.

I did ask and all I got is there are old errors in the journal which do not relate to the issue, as soon as I left the garage it started doing it again, I am lost I do not know what to do please help? I was thinking about changing the fuel filter with the major service which is due anyway.

[GiveMeABreak]

I understand that - the journal can record historic faults, but your screenshots are after the result of a new Global Test, so are not historical. There's nothing I can do here with this number of faults - there are simply too many, so either the vehicle data networks or one of the main ECUs / supplies units have a fault leading to the creation of ghost faults, as I can't see this many faults being realistic.

[sofnet2000]

I understand that - the journal can record historic faults, but your screenshots are after the result of a new Global Test, so are not historical. There's nothing I can do here with this number of faults - there are simply too many, so either the vehicle data networks or one of the main ECUs / supplies units have a fault leading to the creation of ghost faults, as I can't see this many faults being realistic.

So I can not be wrong in saying that the ecu is faulty? and need reprogramming or replacing?

[GiveMeABreak]

That's unfortunately not the case either - because the vehicle uses multiplexed electronics and data networks. Very simply put, encoded signals are sent along various CAN data networks. Systems are categorised according to priority, so that safety critical systems are on a higher speed / priority network than say the comfort systems. The interconnected ECUs determine whether the data is meant for them and they also send their own data destined for another ECU.

So imagine much like a computer network, if the cabling is damaged, shorted or has other issues, then this can result in non-communication with the ECU in the worst cases or garbage being passed along or one ECU not getting data that it expects or needs - and in such cases that can cause the other ECUs to throw up errors themselves when there may not be a problem with the equipment it is responsible for, but the data that it needs is not there or not making sense.

That's why it needs proper testing to see if it is indeed a main controlling ECU at fault (like the engine ECU or the BSI for example) or whether this is a problem along the data networks. You don't want to be replacing parts when there is no need and ECUs are not cheap.