Hey guys,

I have a 90hp 1.6tdci (hdi) mk6 fiesta running a gt1544 hybrid (49mm comp wheel). The car has run flawlessly for around 1 month since finishing up the tuning. Running 1.75 bar of boost and 75mg. The car however developed a boosting issue quite literally overnight.

No boost in 1st gear, excessive lag in second (boost comes on like an on/off switch). Then 3rd, 4th and 5th not quite as bad, but the boost comes on very aggressive. (it was much more linear before and a lower/faster spool)

The car is running mafless, no boost leaks. No vaccum leaks and I replaced the n75 electro valve.

Before I pull the turbo and get the vanes inspected, is there anything else you guys could advice/suggest?

Your help would be very much appreciated!