Hello everyone!

I'm having some trouble with my 2004 VW POLO 1.4 FSI (engine code AXU) and i'm hoping someone might be able to help me.

The car refuses to start most of the time (90%) at the first key and it takes several tries for it to actually start. Sometimes it starts wonderfully, sometimes i have to spend 10 minutes trying to start it in order for it to start.

When it does start, the idle fluctuates. Not a lot... But enough to make the whole car shake like the engine is beginning to stall. It never actually stalls but the RPM dips from around 700 RPM to around 600 RPM, then it goes back up and then it dips again and so on and so on. If i'm actually driving it, the engine works normally.

Here is a short video of the starting trouble i am getting:

POLO 9N 2004 1.4 FSI AXU starting issues. - YouTube

The ECU doesn't have any errors whatsoever and i've taken the car to several mechanics and neither of them couldn't identify what was actually wrong with the car. Each of them gave a best guess that the next mechanic i went to, in hopes for a more definitive answer, quickly dismissed.

Until now i've heard the following possibilities.

- Something electric, like a cable snapped in the harness (but that would not allow the car to start at all)
- Injectors (but that would make the engine run erratically when driven)
- Fuel pump (But i can hear it work every time i put the key in and if it were the fuel pump, the car would also not start at all)
- Fuel injection high pressure pump (Again, the car would either not start at all or the engine would stutter and stall while driving)
- Timing chain (2 different mechanics checked out the chain and confirmed it was okay)
- Cam shaft issues
- Throttle body needed cleaning (done that, still no improvement)
- EGR valve (also cleaned, no improvement)
- Catalytic converter (replaced)

I have already invested a lot more money in this, than i have actually spent on buying the car...

Can someone please help me with some advice? I can't sell it in this condition and i'm also afraid to take it out for a drive, fearing that i will have to leave it somewhere in the middle of the street if it dies completely.

Thank you all in advance!

I'm really looking forward to any type of advice you may have on this.