Cold starts - secondary air injector pump?

[JonP01]

Jon, I have the exact same polo as you, Candy White, manual 77TSI. I'd love to hear this noise you are talking about, to see if mine also does it..

There is a very easy way for me to reproduce it 100% of the time without fail in my car:

1. Drive the car from cold for around 20 minutes so it is thoroughly warmed up. This is critical, because until you have driven for this long and engine is 100% fully warmed up, you don't hear anything - it is perfectly fine, just like it was for the first 18 months. The first 10 minutes when I drive the car it is great. No funny noises.

2. Ensure all windows are wound up, stereo and air flow fans / aircon is off.

3. Find a quiet back road with inclines so that you will have to work the engine a little bit and also so there is no traffic to mask the sound.

4. Lightly accelerate the car up the incline in either 3rd or 4th gear at around 1,200 RPM to whatever is the legal speed limit, using around 30% throttle.

When you do this, on my car you will hear a very distinct metallic sucking sound when the throttle is opened. It will stop when you close the throttle. Sort of like an industrial sized coffee percolator but with very metallic flavour as if there is a dry bearing or maybe like a steel roller being rolled over (lightly) sand-covered concrete.

The car will then continue making this noise for the rest of the drive and even after you have gotten home and the car is at idle with no load at all. Infact you can check it here as well. After the drive, open the bonnet and put your ear facing downwards towards the gearbox overlooking the inlet manifold end of the pipe from the turbo to the inlet manifold. You will still hear that steel roller over sandy concrete sound even at idle.

It is absolutely unmistakable unless you are all but deaf (or your car does not have the problem). The technician quite clearly heard it as well and said it was normal, but did not explain to my satisfaction as to why it started suddenly and the car never made it for the first 18 months prior.

The above steps are just so you can learn what to listen for. It is sufficiently loud that the only way you don't hear it is if there is thick moving traffic surrounding the car or you have the stereo at unhealthy levels.

What I do agree with the technician now that I have analysed it more is that although the water pump does sound the same, it is definitely coming from where he said - whatever that thingy is between the end of the turbo pipe and the inlet manifold (the technical term for the area concerned is the funny round black plastic thingy at the end of the long black tube coming out of the turbo . He did tell me what it was but I have forgotten the name).

My concern is not only that something is about to break, but whatever breaks might causes something even more expensive to fix. And also that no one would buy the car if they heard it because like me they will just think something is about to break on it. I just can't believe this sound really is normal, despite what VW tells me. If it was, no one would buy the cars. I certainly wouldn't have if I had heard it on the car I test drove.

[LukePolo]

There is a very easy way for me to reproduce it 100% of the time without fail in my car:

1. Drive the car from cold for around 20 minutes so it is thoroughly warmed up. This is critical, because until you have driven for this long and engine is 100% fully warmed up, you don't hear anything - it is perfectly fine, just like it was for the first 18 months. The first 10 minutes when I drive the car it is great. No funny noises.

2. Ensure all windows are wound up, stereo and air flow fans / aircon is off.

3. Find a quiet back road with inclines so that you will have to work the engine a little bit and also so there is no traffic to mask the sound.

4. Lightly accelerate the car up the incline in either 3rd or 4th gear at around 1,200 RPM to whatever is the legal speed limit, using around 30% throttle.

When you do this, on my car you will hear a very distinct metallic sucking sound when the throttle is opened. It will stop when you close the throttle. Sort of like an industrial sized coffee percolator but with very metallic flavour as if there is a dry bearing or maybe like a steel roller being rolled over (lightly) sand-covered concrete.

The car will then continue making this noise for the rest of the drive and even after you have gotten home and the car is at idle with no load at all. Infact you can check it here as well. After the drive, open the bonnet and put your ear facing downwards towards the gearbox overlooking the inlet manifold end of the pipe from the turbo to the inlet manifold. You will still hear that steel roller over sandy concrete sound even at idle.

It is absolutely unmistakable unless you are all but deaf (or your car does not have the problem). The technician quite clearly heard it as well and said it was normal, but did not explain to my satisfaction as to why it started suddenly and the car never made it for the first 18 months prior.

The above steps are just so you can learn what to listen for. It is sufficiently loud that the only way you don't hear it is if there is thick moving traffic surrounding the car or you have the stereo at unhealthy levels.

What I do agree with the technician now that I have analysed it more is that although the water pump does sound the same, it is definitely coming from where he said - whatever that thingy is between the end of the turbo pipe and the inlet manifold (the technical term for the area concerned is the funny round black plastic thingy at the end of the long black tube coming out of the turbo . He did tell me what it was but I have forgotten the name).

My concern is not only that something is about to break, but whatever breaks might causes something even more expensive to fix. And also that no one would buy the car if they heard it because like me they will just think something is about to break on it. I just can't believe this sound really is normal, despite what VW tells me. If it was, no one would buy the cars. I certainly wouldn't have if I had heard it on the car I test drove.

So i did exactly what you did above, and i cannot reproduce the noise at all. The only noise i get is the turbo opening up in the optimal torque range. I think you have an unusual case.

You have done the above and then taken it straight to vw wether you have an appointment or not, right?

[JonP01]

So i did exactly what you did above, and i cannot reproduce the noise at all. The only noise i get is the turbo opening up in the optimal torque range. I think you have an unusual case.

You have done the above and then taken it straight to vw wether you have an appointment or not, right?

Thanks for testing this out for me Luke. Yes, I did exactly as I had described above then had the technician take a ride with me where we reproduced the noise precisely. He could easily hear it and fully acknowledged it. So there is no argument that it is there. He told me it is normal. When I asked how it could possibly be normal when it had never made the noise for the first 18 months (and that it is now really annoying), he explained that it was because the engine and turbo had now "opened up" and that the turbo was mounted very high under the bonnet line, making it louder. He also would not entertain my argument that the sound started suddenly (as in a split second when it was not there and suddenly there all the time). To me, that fact alone belies it being "normal".

I protested all of that for two days before giving up on them, as they are obviously not going to budge from the "normal for the model" line.

So now my Polo has gone from being perfect two weeks ago to:

1. Noisy rattles from turbo actuator, which they apparently now have no fixes whatsoever for.

2. Water pump screams like crazy during cold starts and is noisier than it used to be when the car is warmed up.

3. Inlet manifold is making metallic dry bearing type of sounds even under the lightest of engine loads. Is only inaudible when throttle is closed and the car is going down hill.

4. And as soon as I got it back from their "service" (oil filter change and ECU update), the feeder pump in fuel tank produces a loud, permanent hum easily audible from within the cabin even if I wear 20 decibel ear plugs and the engine is on!

So I am not really happy. 4 things that whilst not stopping the car from functioning are nevertheless extremely irritating and detract significantly from the quality ambience that the car used to have. Now it is even far worse than my old Mazda 2 in terms of irritating noises, and that is really saying something.

Having also had my very first dealings with VW for an actual problem, I now know what they are like. I really regret buying this car, not so much for the things that have gone wrong with it in the last two weeks (though for 4 things to go wrong in such a short space of time is a worry) but for the fact that VW flat out refuse to acknowledge there is the slightest problem with it and thus clearly don't seem to have any respect for what a warranty is or what their obligations are under it.

[Frankie Fazer]

I found this.. i have the same cold startup feature with my Polo late 2013 TSI it sounds awful until its warm and then seems to go away... but i looked at heaps of youtube "noises" for the polo and this could be the simple solution..

http://youtu.be/x_capLXhq_k

[JonP01]

LOL that almost looks like a metal clothes peg or folder clip. I'd almost try it myself if it were possible to get at that end of the actuator. I could try a clothes peg on the shaft just to see if that really is the noise but my guess is it would melt. I still don't really get why my car is fantastic from 1 minute after a cold start and then for about 10 minutes after that. I would have thought the actuator would be shaking around whether the car was cold or fully warmed up.

Excluding the fuel feeder pump which in the last four days has become a permanent fixture of my Polo Symphony in A major (given the feeder pump hums at 440 hertz), it's perfect in that small window of time. Then all the annoying and worrisome noises start. Sadly, another new noise started yesterday just as I thought the cacophony could not become more complex than it already is. Now there is an additional part in the symphony for Glockenspiel. Now I get a metallic ringing or scraping sound whenever I close the throttle. It's exactly like squealing brakes, except that I don't have my foot on the brake. So now I can enjoy sounds both on throttle, off throttle, hot, cold - you name it, it doesn't matter. There is a sound for every occasion!

I would hope that the next person who owns my car next time is either deaf or a fan of John Cage. But even then my concern would be how does a deaf person ring VW Assist or the NRMA from a mobile phone in a broken down car?

[tay113]

LOL that almost looks like a metal clothes peg or folder clip. I'd almost try it myself if it were possible to get at that end of the actuator. I could try a clothes peg on the shaft just to see if that really is the noise but my guess is it would melt. I still don't really get why my car is fantastic from 1 minute after a cold start and then for about 10 minutes after that. I would have thought the actuator would be shaking around whether the car was cold or fully warmed up.

Excluding the fuel feeder pump which in the last four days has become a permanent fixture of my Polo Symphony in A major (given the feeder pump hums at 440 hertz), it's perfect in that small window of time. Then all the annoying and worrisome noises start. Sadly, another new noise started yesterday just as I thought the cacophony could not become more complex than it already is. Now there is an additional part in the symphony for Glockenspiel. Now I get a metallic ringing or scraping sound whenever I close the throttle. It's exactly like squealing brakes, except that I don't have my foot on the brake. So now I can enjoy sounds both on throttle, off throttle, hot, cold - you name it, it doesn't matter. There is a sound for every occasion!

I would hope that the next person who owns my car next time is either deaf or a fan of John Cage. But even then my concern would be how does a deaf person ring VW Assist or the NRMA from a mobile phone in a broken down car?

Hi,in my case ,VW workshop reckon it was the high pressure fuel pump and I got that changed.it was quiet for roughly 6 months and the light rattling noises back.its 80% mostly heard when engines cold.