I have had a 2014 1.6 TDI MkIII Octavia for almost a year now.

 

I am wondering if I just broke the fuel pump.

 

While I was rooting around in the engine yesterday trying to find where the oil filter was located, I pulled a few times on the black plastic cover on the fuel pump.  It's that black cap shown top left in the attached photo. I know this was stupid, but I initially thought it was just a snap-on cap for the oil filter.   Anyhow, it seemed pretty firm when I first grabbed it.  After an initial bit of wiggling it was clear that it wasn't going to budge. And then it did.  I heard an internal "crack", and now the whole cap wobbles a bit (maybe 1mm of play in all directions). I stopped then, thankfully, realising how stupid I'd been.

 

But what I don't know is what that black plastic cap does.  Is it making any critical air / fuel seal that I've now broken?

 

Or is it just some kind of anti-tamper dust cap that doesn't really matter now that it's wobbling.

I can't find any pictures on the web of what's under that part.

 

Please tell whether I've just broken my fuel pump and will have diesel sprayed all over the car if I start it up ...

Have you tried starting the car at all?

Just now, Stuart-h said:

Have you tried starting the car at all?

 

I haven't started it yet  - though mainly because I'd taken the oil out before I later found out that I couldn't get to the filter.

 

To be honest, though, I'd be happy to restart the engine as soon as I've put the oil back.  I don't expect to see a sudden fire or anything.  But I'm more concerned about the longer term safety -- I don't want my wife driving the kids on the motor way later in the month to have the car conk out on her etc ..... 

 

So I'd like to know what I've broken. This black cap must do something ....

I put the new oil filter and oil in the car today, after which I could start it up.

Nothing is obviously leaking out of the fuel pump or misbehaving.  So the black cap is not 100% mission critical.  But I still wonder what it is for ....