Hi All,

My 2020 ford focus 1.5 TDCI 120 has an issue that no one can diagnose. It runs really badly when cold - chugging intermittently mostly in lower gears.

The EGR and MAP sensor were found to be heavily sooted so we got it the EGR replaced and the sensors cleaned.

Ford also recommended changing the injectors :( so that was done as well the fuel and oil filters.

The DPF has been removed and cleaned too but nothing has changed - the issue is still the same.

There are no error codes and the car has done 120K miles.

I've been feeding Forscan data into an AI tool and it thinks it might be this ??
Sticking Variable Geometry Turbo (VGT) Vanes

Thanks !

This would certainly affect running and might free up as the engine warms but I would check the fuel pressure regulator and find out if it is giving the right pressure at low engine speeds.

Welcome!
That's quite a high mileage for a car of that age.
AI may or may not be right so change the turbo at once!
(NO, don't guess, TEST, you've already been a victim when the injectors and DPF cleaning were done etc, etc, on a "We think")
Apply a vacuum to the actuator and see if it moves or better, disconnect if possible and ensure the vanes move easily then work backwards to the actuator then the vacuum pipes to the valve that actuates the actuator (if you see what I mean) then test the actuator solenoid valve for resistance and it's performance i.e. when actuated, does the vacuum flow correctly and stops when released as in @Ford G2008 's excellent thread:
https://www.fordownersclub.com/forums/topic/166556-turbo-boost-fault-limp-mode-solved/
I suggest you try that route first unless someone can go straight to the root of your problem by magic or otherwise?
From above, fuel rail pressures (demanded vs actual are also a crucial test)

The problem with AI guesswork is that it represents the sum of all guesses, most of which are likely to be wrong.

No one reckoning glow plugs??

Thanks for all the replies guys.

The issue still happens when the engine is warm just not as badly so we weren't thinking of glow plugs. This is a forscan reading from when it is chugging badly.

This was why we were suspecting the EGR in the first place - it was also badly clogged. The garage did use a remanufactured DRI EGR valve too.

i bet those injectors werent cheap. funny how they throw in something expensive without properly diagnosing it.

Do you have engine loight? does it go in to limp mode?

Cleaned MAF and checked for air leaks post MAF?

To me, Forscan indicates issues with the EGR desired v actual AND boost actuator plus the MAF values are therefore strangely different which may be indirectly pointing to those other control issues?
Anyone else see that?

Were the EGR adaptations reset?

MAF and MAP were cleaned, MAP was heavily sooted. EGR adaptions were run multiple times by Ford.

So weird that there are never any DTC codes thrown.

Agree about the weirdness, although the heavy sooting may still be building up due to whatever fault may still be present evidenced by the chugging (if still present and unchanging?)
What about any observing and testing of the boost actuator system (all of it)?
AI may yet be right?

Finallly got this resolved in another Ford dealer. The injectors were programmed incorrectly with two of them being swapped. They reprogrammed and the issue is gone.

42 minutes ago, Bazfhdr said:

Finallly got this resolved in another Ford dealer. The injectors were programmed incorrectly with two of them being swapped. They reprogrammed and the issue is gone.

Do you know if that was the original issue to begin with?

Original problem was probably the injectors, they leak tested them and found two failing.