I have a 2007 SE 2.2 TD4.... BUT, she had an engine replacement back in 2015. Is there any way of telling if she's got the 150 hp, 160 hp or the SD4 engine?

The SD4 is 190 Hp. Unless you had the engine complete with all ancillaries fitted, I’d say you still have a TD4 160hp engine. Past: FL2 TD4 HSE Auto
Evoque SD4 Dynamic Lux Auto
Present: Audi A3 S Line.

You should be able to tell what engine you have from the engine number.(If you can find it!) During an engine swap it is very common to re-use a lot of the original ancillaries like exhaust ,turbo, manifolds, etc, either because the engine didn`t come with them or because the wiring connections etc are different on the replacement engine. If that has happened it probably has a power output the same as it was originally regardless of what replacement engine got fitted.

Appreciate the responses guys! Engine number DZ594017701224DT if that means anything to anyone?

Looking at a Bluespark and want to make sure I'm getting it for the right engine.

I am guessing this and that the displacement is exactly the same be it this or that. Changes in power output will be down to other influences. FL2 MY10 TD4 GS traded in at 2 years
FL2 MY13 TD4 GS Current

224DT engine is the 150Hp version. so get a Bluespark to suit that engine and you should be fine.

Awesome. Thanks Don.

I thought that there are some differences between the TD4 pre 2011 (no DPF and organ pipes on air intake pipe), post 2011 TD4 (with DPF, no organ pipes and some changes to injectors and turbo) and SD4 different again. In other words it's not just software.
We had both a 2010 TD4 and a 2011 TD4 at the same time and they felt very different to drive (later one had a lot more torque) 3 x FL1 2 manual + 1 auto
5 x FL2 4 manual + 1 auto
Now Discovery Sport P250 MHEV SE