My 2016 Fabia (CUSB engine) had had this problem for a while now where when I start my car my engine light is on but it drives fine I get boost it doesn’t feel like it’s over boosting just normal. Then after a while of driving the glow plug light flashes my stop start doesn’t work and there’s no more boost I assume this is limp mode. Sometimes it just happens when I drive sometimes it happens when I have a bit of a heavy foot and as I’m accelerating quickly it just cuts boost and there’s have been times where it happens if I do a few short journeys in a short space of time where I switch the car off and then on again in a short period of time. I have done drives over 3 hours before without it going into limp mode at all though so I can’t in point why this is happening. My OBD reader come us with codes P2563, P2564 (Turbocharger boost position sensor circuit A low) and occasionally P0299. Anyone have any ideas what this could be specifically I’ve had a few sensors changed and nothing has worked a garage has told me I need a completely new turbo but one I don’t think that’s right and two I don’t have over a grand to throw at it right now, it seems to be the actuator but I’m not too sure. Any help would be appreciated sorry for the long rant just thought it best if you knew anything from the off.

Hi, welcome.

Have a look at videos for turbo actuator replacement on VW diesels for possible P2563 (and possibly other two if related). I'm just going with the flow here, I'm not a mechanic, only going on the limited information of your post and assuming your scanner is giving correct error codes.

Other with much more knowledge may also post.

Good luck.

Check any vaccum lines to turbo and also if the actuator is moving freely. My old 1.9tdi actuator was sticking and used to over boost then limp mode. P0299 is underboost so wonder if its sticking open randomly. I lubricated mine and moved manually for a good while till it became smooth again. I think theres a sensor on yours that may be failing or perhaps wiring to it. The turbo may be a variable vein type and they can get carboned up and stick causing the same symptoms. Also check your air filter.

Alasdair

Thanks for that I’ll have a look, I’ve used my scanner and a garage used theirs and got the same readings so they should be correct just don’t directly tell you the exact issue. I changed the air filter this morning so going to see if that helps. I suspected it might be the actuator as I’ve seen other people saying similar things so will try and have a look just not an easy car to work on with all the turbo trapped between the block and under where the dash is.

17 hours ago, Bry21 said:

just don’t directly tell you the exact issue

No they don't always/usually/often, the scanner is another, often more detailed, diagnostic tool, like a multimeter and your human senses, knowledge and experience, like all information from any source it needs to be checked and cross reference for being applicable and accurate.

Unless the air filter (and/or air filter box and trunking) was badly clogged up the filtering should be Ok for a diesel but timely thorough servicing and use of good quality engine oil and perhaps V-Power type diesels will help a lot as will getting your clog down occasionally Italian tune-up style as you've mentioned.

As much of car service, maintenance and some repairs boils down to clean and lubricate (engine oil change, air filter, V-power type fuel, clearing error codes, etc..) I agree with suggestions of looking at and attending to the physical matters, cleaning, lubricating and working the actuator, checking wiring and connections. You might have to replace the actuator (or part of it?) or you might not, engine bays can be dirty place very particularly diesels so start with removing the dirt if there's a lot of it, you'll want the area, and connections, clean to fit a new part anyway.

Don't just rely on the sexy toys like scan tools also cover the start basics (which you often have to go back to anyway with scan tool results).

Good luck, let us know how you get on.