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Oh yes. It's the principal difference. The TDI 90 has a wastegate turbo, the TDI 110 (and all subsequent diesels) have a VNT turbo.
Instead of spilling pressure at high revs. the VNT turbo is sized to make use of the full gas flow at maximum revs, to spin the turbo to give max rated boost under those conditions. At lower revs, when there is less gas flow, less volume of exhaust gas, there are aerodynamically-shaped vanes in the turbine inlet (between the exhaust manifold and the turbine itself) which rotate to narrow the inlet, which makes the gas flow speed up (same mass of gas, smaller opening, so bigger velocity). The increased velocity keeps the turbo spinning at a high enough rate to compress the inlet charge, keeping the boost up.
This system, controlled by the ECU to keep the inlet charge compression as close to optimum as possible, delivers usable boost over a wider rev range than the wastegated turbo, and makes the engine more efficient. Which means that the TDI 110 delivers more performance and better fuel economy - a win-win situation, most rare in automotive technology. The turbo is slightly more complicated but still extremely robust and reliable. The most frequently reported downside is that, if the car is mainly driven at modest speeds (e.g. urban commuting, stop-start, never getting to high engine revs) soot can build up in the exhaust turbine and jam the vanes. The remedy is an Italian tune-up, give the engine a sustained period of load at high revs to get the turbine hot and try to burn off the carbon.
Whoops, meant to add - there's a picture of the vanes in operation at the bottom of this page:
http://www.technologie-entwicklung.de/Gasturbinen/VNT15-Turbo/body_vnt15-turbo.html
Er. Hopefully you wanted to know all that. Yes, I have a TDI 110 (Toledo in fact) and used to have a TDI 90 Ibiza. So I have a bit of previous.
By the way, it's a bit pushy to complain about not receiving an answer after half-an-hour. There's no reason for anyone to answer other than a desire to be helpful, on the assumption that someone will be helpful in return at a later date. No forum is awash with experts just waiting to answer a random question (that has been asked dozens of times before, too, in most cases). In your position I'd have waited a day at least, probably two or three, before booting the thread.
Instead of spilling pressure at high revs. the VNT turbo is sized to make use of the full gas flow at maximum revs, to spin the turbo to give max rated boost under those conditions. At lower revs, when there is less gas flow, less volume of exhaust gas, there are aerodynamically-shaped vanes in the turbine inlet (between the exhaust manifold and the turbine itself) which rotate to narrow the inlet, which makes the gas flow speed up (same mass of gas, smaller opening, so bigger velocity). The increased velocity keeps the turbo spinning at a high enough rate to compress the inlet charge, keeping the boost up.
This system, controlled by the ECU to keep the inlet charge compression as close to optimum as possible, delivers usable boost over a wider rev range than the wastegated turbo, and makes the engine more efficient. Which means that the TDI 110 delivers more performance and better fuel economy - a win-win situation, most rare in automotive technology. The turbo is slightly more complicated but still extremely robust and reliable. The most frequently reported downside is that, if the car is mainly driven at modest speeds (e.g. urban commuting, stop-start, never getting to high engine revs) soot can build up in the exhaust turbine and jam the vanes. The remedy is an Italian tune-up, give the engine a sustained period of load at high revs to get the turbine hot and try to burn off the carbon.
Whoops, meant to add - there's a picture of the vanes in operation at the bottom of this page:
http://www.technologie-entwicklung.de/Gasturbinen/VNT15-Turbo/body_vnt15-turbo.html
Er. Hopefully you wanted to know all that. Yes, I have a TDI 110 (Toledo in fact) and used to have a TDI 90 Ibiza. So I have a bit of previous.
By the way, it's a bit pushy to complain about not receiving an answer after half-an-hour. There's no reason for anyone to answer other than a desire to be helpful, on the assumption that someone will be helpful in return at a later date. No forum is awash with experts just waiting to answer a random question (that has been asked dozens of times before, too, in most cases). In your position I'd have waited a day at least, probably two or three, before booting the thread.
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thanks muttley
very indepth explanation but appreciated. What it is I went to get the lower intercooler pipe from a scrapyard today was of a 2001 leon 1.9 tdi same year as mine and everything. Got the pipe looked under my car to find where the pipe secures to top of turbo my pipe work is horizontal and I remember the one at scrapyard was vertical bummer didn't pay much for pipe just thought that the one at scrapyard must have been a 90bhp tdi 
There's every chance the scrappie had a TDI 130, a PD engine with different pipework. The best way with scrappies is to take the bit you want to replace in with you (make sure they register it before you go in or they'll charge you for it on the way out). Then you can match it up for yourself.
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