Hi everyone,
I'm a bit desperate and would really appreciate any advice. I'm a girl and I really need this car for work. My car is a Seat Arosa 1.0 (AUC engine), which is basically the same as a VW Lupo 1.0 and very similar to the Polo 6N.
Whenever I turn the key to the ON position (before cranking), there has always been a very distinctive buzzing/humming noise from the front of the car. It's fairly loud and lasts about 2-3 seconds. It has done this every single time since I've owned the car and it was normal for me.
Last Monday the check engine light came on. However, the car drove perfectly normally all week (Monday to Saturday). On Saturday I parked it in my garage.
Then on Monday, when I tried to start it again, it wouldn't start. The strange thing is that the first time I turned the key, that familiar buzzing noise sounded much louder, deeper and rougher than usual. After that, the engine never started.
Since then, every time I try again, that buzzing noise has completely disappeared. I can still hear the relay clicking, but that original 2-3 second buzzing is gone.
So far I've checked:
- All fuses are OK.
- I removed the fuel pump cover and recorded a video. The fuel pump does make a small humming noise when I turn the key, so it seems to be getting power.
- I checked the timing belt just in case, but it was replaced about 6 months ago and looks fine.
My brothers think the fuel pump is failing, but I'm not convinced because I can still hear it running. The problem is that the sound I'm missing is different from the fuel pump's small hum. The missing sound was much louder and seemed to come from the front of the engine bay.
The stored DTCs are:
- P0135
- P0171
From what I've been told, neither of these codes should suddenly prevent the engine from starting, especially since it drove perfectly for almost a week after the check engine light came on.
I'm trying to diagnose this without spending a lot of money replacing random parts.
I'm attaching several videos so you can hear the sounds I'm talking about.
Does anyone know what that 2-3 second buzzing noise could have been? Is there anything else I can test at home with basic tools before buying parts? While searching through forums, I found someone with a very similar problem and in their case the car would start again simply by adding more fuel because the fuel level was too low. I haven't tried that yet, but I'm also very low on fuel although I've been there other times without issues, it can be seen in the videos.
Any ideas would be greatly appreciated. Thank you so much!