UK-POLOS.NET - THE VW Polo Forum

Hi

while testing a newly fitted airfilter in the garage i noticed 2 weird noises from my engine

1: engine is now where near running temperature. i start the engine. don't give gas or anything.as i cut it off there's a hissing sound that seems to come from the throttle body/injectors area. i even tried it with no airfilter attached and still does it. however if i cut off while slightly giving gas (barely enough to rev it) it shuts off normally

2: when i turn the key without starting the engine there's the usual brief injector/fuel pump sound then there's a sort of bip that lasts a few seconds before stopping. it also seems to come from the throttle body/injectors area.


car is a 1.0 polo 6n and engine is untouched besides the induction kit


help please

ok so i found the source of the hissing sound. i assume its the vacuum pipe. the problem is i cannot locate the other pipe it's supposed to connect to. where am i supposed to look for it?


my findings:

the greenish thingy (what is it btw?) seems to be missing a pipe(which i haven't been able to locate till now)

another view


any pics will be a huge +

Hissing could be a coolant leak as you said its near the warmed up temperature, so check your coolant and see if its dropping.

I member there where two cables/pipes that went to the standard filter box, one a vacuum pipe (black one I think) and the other red one. I noticed no difference when they where disconnected at all so I doubt they are your problem. One went to a T connector (which will have a little cap on if your car has no air con) and the other one went somewhere else, can't member.

As for problem number 2, it could be an aftermarket alarm system or C/L that making that noise, when you turn it to the first switch position you allow the car to power all divices, so it could be some aftermarket electronics?

about the 2 pipes from the stock box, was it a big one (like 1 1/2cm in diameter) and a smal;ler one? if yes the smaller one seems to be the one hissing. but any idea about the green thingy in the first pic?

for number 2 there's no after market electronics on the car but i suspect it is related to number one


thanks for the reply

dont worry about the hissing when you switch the car off is just the open filter. all do it.

and you sure the bip wasnt their before but never realised before now?

you're sure? it evens does it with the airfliter off and didn;t do it before. and i can sens air coming out of the green thingy as i shut off


the bip was definitly there before but it just lasts way longer now

buzzing sound comes from this



i know its normal to buzz but it does it way longer than before.any ideas


and again


what is it and where does the pipes are supposed to be connected? the one connected goes to a T connector (as mentioned by polosib). where does the other end supposed to go? can i just shut it close with a screw or something?

the hissing when you turn it off is normal.

definatly. is just the air coming back up after you have shut it off everycar with an open filter or no filter will do it.

the little green thing is a vacuum. they is a few they go to the bottom of the airbox when it is on.
think they for the auto choke.


it clicks from around throttle body because it is injecting.

it may stay for longer beacause it now has an open air filter and air mass meter is detecting the engine is getting more air so will inject more fuel hense why stays on a litle bit longer.

if it isnt causing any problems dont worry about it.

thanks


one final question.

can i plug it? i mean tie it down just to stop that noise

yeah is you wish too lol

ok

thanks for the help guys