I have had a fault on my car for a while now, it has been to my mechanic who i trust and is normally very good with these things but we can not seem to get to the bottom of the fault. The usual engine management light has come on with the yellow '' curly wire '' as i call it coming on, it tends to happen when the car is under load or in a higher gear than it should be. He has had the usual code machine on it and due to this he has changed a small plug which i understand measures the DPF gases, he did tell me the exact name of it but i can not remember..... the fault is still happening and we are at a loss really as this small white plug is the the only real thing that is in the loop so to speak, we even changed the same plug just in case it was a faulty one but no luck.

 

I can find out the real name of this sensor tomorrow but any ideas in the mean time. Ta

The 'curly wire' is most likely to be the glow plug light. Is your mechanic scanning  the codes with VCDS?

Lambda sensor.

We have just had the glow plug (curly ➿) light flashing on our new to us 2010 1.6 crtdi, we have so just had the exhaust gas sensor changed which is just after the turbo... Luckily our light hasn't come back on, but this morning it went into a sort of limp mode and ran lumpy but no fault lights came on

Had a similar fault and car went into limp mode. Mine was a couple of faults, namely one of the connection leads to a glow plug 4. These leads are easily damaged. In addition, new exhaust gas sensor No 4, Bank 1. Also did force regeneration on DPF. Touch wood, been fine since. VCDS essential to scan for faults first.