Engine lost power on motorway last week.. Looked up the code which is p0299 says its low pressure from turbo output... Checked pipework and cant any splits or cracks. Does this mean my turbo is a goner? What other things should I look at? Iv started the car the car today and it cuts out almost Immediately? 

Potential causes of a P0299 turbo underboost code include:

• Intake (induction) air restriction or leak
• Failed or damaged turbocharger (sticking, binding, etc.)
• Faulty boost/charge pressure sensor
• Faulty wastegate bypass regulator valve

Read this and this

Where is the boost/charge pressure sensor? Thanks