My Skoda CR vRS Diesel went into limp home mode under load. At first the flashing glow plug light, which cleared after the ignition was turned off, but the car still felt sluggish, and then the locked in limp home mode. I read the codes with Carista and it is P0299 Under boost. I checked all the pipes etc. for leaks to no avail but after reading a post elsewhere, I removed the rubber pipe from the N75 to the actuator and sucked. My understanding is that the actuator should hold pressure and if you suck you should feel resistance, and be able to block the pipe and feel residual suction. I had none of this - it was easy to suck. Am I right in my assumption that the vacuum on the actuator is knackered and a new actuator should cure things?

The diaphragm is split in the actuator, there is a repair kit so you can replace just the actuator.
You need to adjust the actuator rod exactly the same as the original so you don't cause any calibration issues with the position sensor.
There is an adaptation function in vcds to reset the sensor calibration if there is a problem, this will work if close to normal parameters.

Dave

That’s great - thanks!

From what I am reading, the job is a bit of a pig to do.....might find a good independent!!