Is my fuel pump dead??

[Nino]

Hi all, I am hoping that someone can shed some light for me.

My car when I open the drivers door only 2/10 will the fuel pump prime the fuel lines, the other times I have to crank the engine for a few tick overs more before it will start. Once started is will struggle for a second or two then the car is fine. It is also worth noting that the car runs and drives perfectly when started. The other thing I have noticed is if I leave the door open for a few mins I will then hear the fuel pump kick into life and prime the lines.

I have also noticed that only 3/10 times the choak will come on, other times it will sit straight at 600-700rpm.
Natrually I always let the car warm up so this isn't a massive issue for me.

Anyway I have done alot of research, and I have changd the following:
* Checked the fuel pump fuse and changed it.
* I have changed the fuel pump relay.
* I have even put in a brand new door module, I have also noticed that one of the previous owners has also changed the door module for a brand new one less than a year ago. (wish I knew this before changing it)
* I have even changed the ECT.
* The car has had a full major service and even had the plugs changed.

But after changing my door module yesterday, I went out this morning, opened the driver door and no buzzing sound from the fuel pump

I know the module is working fine, as the interior light comes on when door it open, the car chimes if I put the lights on without the key & the puddle light comes on and the door locks perfectly fine as it did before I changed the door module.

I am starting to think now that it can only be the fuel pump itself? I also noticed quiet recently that if I have no music on, I can hear a slight which can only be discribed as a electronic wuring noise coming from the rear of the car, near where the fuel pump is, only apprant when the car is running.

It is also worth noting that I have noticed that if the car has half a tank of fuel or more, although I still don't hear the fuel pump priming the lines I don't have an issue with the car starting at all, I.e. I don't have to crank the car more than needed.

Also this only happens if the car has been sat for more than a few hours, i.e. the engine is cold.


This is lead me to think that the only thing that could be causing my issue is my fuel pump? Which confuses me as the car runs perfectly fine so my thought process on this lead me to think that if I had a faulty fuel pump, surely I would have running issues?

[WadGTI]

I take it you changed the fuel filter too?. Not had pump issues before but by the sounds of it like the pump is becoming unreliable!

Not sure if vagcom has any fuel pump tests you can try first?

[Nino]

Yeah the fuel filter was changed

[rio_gti]

crank sensor 

[Nino]

Wouldn't that cause other issues?

[Wazzzer]

you can do an output test with the fuel pump via VAG COM

[matty james]

that whurring noise is your fuel pump slowly giving up. bad start ups will be followed by what may seem like turbo lag but is infact your pump struggling to supply your engine with fuel at top end acceleration, then it will start struggling to keep your engine running while idle in traffic , then it will die completley-all this happened in the space of 3 weeks to me . on the brightside there an easy diy replace.

[Nino]

you can do an output test with the fuel pump via VAG COM

How do you do this?

[Nino]

that whurring noise is your fuel pump slowly giving up. bad start ups will be followed by what may seem like turbo lag but is infact your pump struggling to supply your engine with fuel at top end acceleration, then it will start struggling to keep your engine running while idle in traffic , then it will die completley-all this happened in the space of 3 weeks to me . on the brightside there an easy diy replace.

Funny you should say that, I noticed last week what seemed to be turbo lag then it was fine the next day.
Are they really easy to replace? I looked at a beif guide and it looked quiet hard to me.

[rio_gti]

I got a working fuel pump in the garage but what part no. is yours?