Ocy 2001 TDI Y reg

The car runs very well 99% of the time, but on occassion, mostly on very steep hills, power fades.

Its as if the turbo isn't cutting in.

.

Once its happened the only way to clear it is switch the engine off !

ECU prob ? pump ? air lock

Any ideas ?

Maf

Vag Com will tell you,I suspect the map sensor as this tell the ecu when there is boost.

PD or Mech injection ?

Common fault on that engine, usually e75 valve failure, power cuts when overtaking or when you realy need it, switch off and on again restores power. If MAF goes power usually stays down. Also check all vacum hoses to turbo and control valves. Easy check is to swap out the e75 valve with a know good one and try it.

Which 1.9tdi is it, 90bhp? 110bhp? 130bhp? If power is dropping when accelerating, and revs approx 3000, then I suspect the VNT turbo issue that is quite common on the 90 and 110 engines. Basically turbo vanes stick open, causing an over boost, so engine goes in to limp mode. Plenty of articles on here about it, have a search.

Many thanks for all your replies !

Its a 90 bhp, and yes power drops around the 3000 mark, but ONLY on hills, and not often ( thankfully)

Yes reading up on this site it seems like an over boost shut down situation.

Found out that the vavles Hoverurb talks about are located on the bulkhead under the windscreen wipers.

Looking into it further into problem.

The http://www.technologie-entwicklung.de/Gasturbines/ site with a turbo strip down and clean ( mentioned on Brisokda ) was useful.