OBD code P0299 & loss of power...

[2CV67]

After a long but gentle drive back from Sicily, I stopped for 15 min at a service station 30km from home to drain the water tanks.
On driving away, there was a very significant loss of power & the preheat warning lamp started flashing.

Switching the engine off & restarting restored normal behaviour.

My Carista OBD dongle tells me I have OBD code P0299 (Turbocharger underboost condition) & engine code 05171 (no idea what that is).

Any useful comments?

Thanks!

 

[calikev]

@vwguru

 

[briwy]

Thats telling you what you already know, lack of turbo boost but doesn't say why. Check all hosrs are on ok first. Do you let it idle for a while when you stop? Ideally you should do this when the turbo is hot to let it cool while still getting an oil feed.

 

[2CV67]

Do you let it idle for a while when you stop?

If I stop for a photo at the top of a mountain pass, then yes, I let it idle.
The rest of the time, I drive so gently the question doesn't arise!

Still can't find what engine code 05171 is...

 

[andyinluton]

I cant find 05171 anywhere.
Using the logic that the codes are grouped with normally a zero at the end meaning it affects the vehicle generally, a 1 at the end means cylinder 1 2 cylinder 2 etc etc - the closest code I can find is 005170. I would suggest its somewhere to start looking.

005170 - Secondary Air Injection Solenoid Valve (N112): Open Circuit

Possible Causes
Secondary Air Injection Solenoid Valve (N112) faulty
Secondary Air Pump Relay (J299) faulty
Possible Solutions
Check Secondary Air Injection Solenoid Valve (N112)
Check Secondary Air Pump Relay (J299)