Audi A4 loss of of power, turbo?

[mattsavage]

Year 2000 Audi A4 1.9 Tdi PD

Hi. I serviced our Audi yesterday, changed the oil and filter, changed fuel filter, changed air filter, checked brakes, tightened slightly loose rear wheel bearing and that was all I did.
Then, I start it up, give it a few seconds to idle then I went for a drive.
No power! Just as if the turbo was not doing anything. I've had this before and it was the air flow meter, so I disconnected that, and still no power.
A while ago I brought a diagnostic reader. So I plugged this in and it came up with,
VAG type 5 digit - 17964
P type - P1556

When I look up 17964 it tells me,
"Turbocharger pressure - upper limit exceeded"

and says the problem could be,
"Turbocharger wastegate regulating valve, intake leak, Turbocharger defective"

All I did was change the filters!!

Has anyone had this problem before? I'm guessing it's something simple.
Any help much appreciated.

Thanks,
Matt Savage

 

[Rev-head]

bleed the fuel system sounds like that is the problem .air in the filter

 

[Administrators]

Hi 17964 is negative not positive make sure that airmass plug and the connecting pipes on the air box are all sealed


17964 P1556 Charge Pressure Contr. Negative Deviation

 

[mattsavage]

Well, I've just opened the bonnet to figure this problem out, and after a lot of looking, checking and messing about, I just happened to notice a thin vacuum pipe at the back of the engine that was not connected! I must have some how pulled it off when I was changing the fuel filter!
So I guess the fault codes were raised because certain things could not actuate.
Anyway, all sorted now. Thank you all for your input.

Cheers,
Matt