Liquid/pump noise when ignition on


Retrofitter - Audi - VW - Skoda - Seat
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Jan 14, 2008
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Coding Something
Guys I'm sure its a fuel pump thing & I think there's a vag coding to do something on the pump but when I go to my car say 1st thing in morning or if left standing for while during day & I go turn ignition on, not start the car, I can hear what sounds like a burst of liquid which I can only think can be fuel pump, its like a noise from say squirting water & this lasts for say 1-3 seconds which I can imagine its got to a pressured point which is why it stops making the noise, I cant think of anything else that would make this noise.

If I start the car & then turn of & then turn ignition on again it doesnt do only after car standing for while which is what leads me to think its a safety/security trait so no fuel in engine when stationary & not used for a while.

Any ideas on the 2.0 TDI DSG, anyone else got this, is it a trait of the 8P?

My 3.2 does it. I think it's just priming the engine so that it is more likely to start quickly when you turn the key.

I think it is a safety feature. Mine does it too.

When you unlock the car and then open the door you should also hear a noise which is the pump turning on.

If you park the car up you may also hear a dripping noise coming from the rear. I reported this on my last A3 and was told it was just fuel being fed back into the tank from the fuel pump.

It appears that it is something to do with not having fuel outside the tank while the car is not in use.
Same here, I turn the car on but not the engine and hear the liquid noise. Then when it is on and I stop at traffic lights for example it makes some liquid like noises, I just assume the car is doing its thing.
aha so I assumed correctly Marc, cool guess its a security & safety feature which makes sense

traffic lights noises are a weird one as I dont hear that, what kinda noises?

Marc havnt forgotten you mate still in the rain fitting sensors kit now, but I'm still thinking of the relay which you could use, I'm sure I know of one thats holds the position, get back to you when done this mate as bumper of still & has to be back on by tomorrow.
aha so I assumed correctly Marc, cool guess its a security & safety feature which makes sense

traffic lights noises are a weird one as I dont hear that, what kinda noises?

I only hear it when I have the air con on low and no radio, makes a pouring liquid sort of sound like fuel or something is travelling through the pipes.

I just thought as long as all the operational aspects of the car are ok and no leaks, etc its just how the car is.
All VAG cars do this it is when you open the door the fuel system pressures itself up and diesels go through the warm up for their start system.
thats strange as mine only does when I turn ignition on not when door opened, also never noticed this on my previous B6 S4, but is it a diesel trait then & surely diesels only go through warm up process when ignition turned on as thats why we have the coil icon in the DIS to confirm system ready, plus draining battery everytime you open the door, giving how many times I do this without ignition on while doing my current batch of mods it cant be linked to the door opening on mine as battery always been ok, but depends on battery current drain for what you say fella, maybe very low current being used, oh well at least I now know its normal, but mines fairly loud, can you guys with same engine/car confirm when window open you can hear the squirt easily?