Hi, Requires a VAG specific scan.
Possibly a faulty coolant temp sensor telling the ECU the engine is colder than it actually is & causing a rich mixture, when it's not required.
Hold throttle on floor next time to weaken the mixtue, to see if it makes any difference.
Hoggy.

 

Would OBDeleven show anything?

 

Possibly. If any related codes then you have somewhere to look; if it doesn't, well, at least you checked.

What are the "starting issues" though? Is it an extended crank? A crank but doesn't run until you try again when cooler? No crank at all at times or when hot?

If it's cranking fine (and new starter motor) then probably not that. New battery usually eliminates that as a problem (and again if cranking, not indicative of a battery issue).

Ignition switch issues is also somewhat common on these so if it's failing to crank sometimes with a new starter motor...that could be switch related. You can use VCDS or OBDeleven to monitor whether the crank signal is being sent from the ignition switch.

Only happening when hot does lead one to believe some type of engine issue as well--whether it be fuel (like evap system) or ignition...

 

Well today I ran a scan with OBDeleven and no errors. Drove the car 40miles to work and though the day I went out and tried starting with no issues. Drove home which was another 40 miles.
As I hardly drive the car... Maybe once a week and sometimes maybe once every 2 weeks. Could it just simply be bad fuel or similar?

 

I would say it's an extended crank.
The last time the issue happened I would hold the key to start, engine would crank for about 5 seconds and then I would stop. Wait 10 seconds and repeat 2 more times just like this. One final go and it worked.
What doesn't help is I can't get it to do it again to try things like Hoggy suggested.

 

Hmm that's an interesting one. I did find this on YT saying it's potentially the HPFP--seems it can be determined by removing the HPFP and checking as shown in the video:

Note this is virtually the same engine as yours with two differences--one it's it's obviously longitidinal as that's a Q5 there; two it has the metal intake because this is a CPMA/CPMB (flex fuel) motor--but otherwise same engine so it could be a similar problem on yours. Little bit of work to remove the HPFP but nothing too crazy--can lookup a video on how to do that if you want to check this.

 

A long crank can indeed be a bad battery. When I bought the TT, the last garage messing with it put in a TT MK1 battery (literally brand new, not even a week old). It would be flat after 10 hours of sitting and cranks were long. I replaced it with a correct varta efb battery and it has worked fine ever since (it wasn't worth spending double for an agm/fleece battery). To be sure the car doesn't have parasitic drains, I updated the telephone preparation module (took about 1h), as I've read that the older software contains a bug which might not put the module to sleep.