TSI squeal noise problem on acceleration

[Guest]

New pump

There is a new water pump/magnetic clutch with a different friction lining that does not make the noise they have been testing it now it has gone out to be fitted to the cars with the noise

[cktsi]

There is a new water pump/magnetic clutch with a different friction lining that does not make the noise they have been testing it now it has gone out to be fitted to the cars with the noise

I actually had an update last Friday when I picked up my car from service. I thought not to post and raise excitement unnecessarily because it seems like we keep hearing about updates for fix release only to find nothing tangible is happening to aussie 118TSI owners.

Since you’ve made the post, I thought may as well share what I have.

Last week VW five dock service centre received written notice from VW that they will be sending parts out and be engaging in a recall campaign for affected VINs. As usual, no timeframe was given on when the parts would be delivered nor when the mailout will be done. They know that it’s a fair number of vehicles that will be affected.

[POLARBEAR666]

It is probably just the friction material that they USED to use on the Golf GT and GT sport.

No mk5's suffer from the squeel as far as I am aware. Anyone know of any mk5's with the issue?

[MariusGT]

i rather enjoy hearing a squirrel yelp every so often when i accelerate!!!



but seriously.. does it affect performance? and aside from the noise being annoying to some people - is it damaging any other parts in any way?

Polar--> didn't you mean MK6's are not affected?

i thought it was a common trait/idiosyncrasy of both mk5 GT/GT Sport and 118tsi?

[idaho]

i rather enjoy hearing a squirrel yelp every so often when i accelerate!!!



but seriously.. does it affect performance? and aside from the noise being annoying to some people - is it damaging any other parts in any way?

Polar--> didn't you mean MK6's are not affected?

i thought it was a common trait/idiosyncrasy of both mk5 GT/GT Sport and 118tsi?

My wife's GT Sport doesn't do it. You just hear the supercharger click in (getting ready for action ??) when you put your foot on the clutch.

From reading the Erwin SSP for the 1.4TSI, the supercharger is engaged a fair bit of the time. Perhaps in the Mk6 VW have changed the engagement strategy in a bid for better economy which has resulted in the cuurent woes.

[cktsi]

From reading the Erwin SSP for the 1.4TSI, the supercharger is engaged a fair bit of the time. Perhaps in the Mk6 VW have changed the engagement strategy in a bid for better economy which has resulted in the cuurent woes.

That's interesting. I've always wanted to know what the real differences were between the two generations of engine. This has given a bit of insight.

[logger]

From reading the Erwin SSP for the 1.4TSI, the supercharger is engaged a fair bit of the time.

From observing the cars telemetry I can tell you that it isn't. The supercharger engages very briefly but quite frequently. Without looking back at my notes I recall it typically engages for between 2 to 3 seconds which to my way of thinking is not at all a fair bit of the time. Be interesting to know what the minimum torque requirement to engage the S/Charger below 2400rev is, because it certainly does not run anywhere near all the time in that rev range.
Perhaps VW changed the friction material in the mag clutch simply to increase its life which would be kind of ironic for them.

[GTom]

No mk5's suffer from the squeel as far as I am aware. Anyone know of any mk5's with the issue?

Yes, and the dealer knows a few others.

I'm having the above work done next Monday.

[cktsi]

From observing the cars telemetry I can tell you that it isn't.

I think he was making the comment in relation to the MkV TSI

I'm having the above work done next Monday.

hey hey... this is new. Which dealer? Did you specifically receive the recall letter?

[GTom]

hey hey... this is new. Which dealer? Did you specifically receive the recall letter?

It's not a recall. I had the issue intermittently and then it comes back for about 5 weeks and goes away. Dealer lubricated the clutch and the noise went away for 6 or so months, then again came back on.

Dealer then basically said (this was before Christmas) that they'll replace it with the new design.

[idaho]

From observing the cars telemetry I can tell you that it isn't. The supercharger engages very briefly but quite frequently...

I think he was making the comment in relation to the MkV TSI...

Yes, I was referring to the BLG engine code version of the 1.4TSI in the Mk5 as described in ERWIN SSP 359. Page 13 in the section Constant boost range of supercharger says "From a minimum torque requirement and up to an engine speed of 2400 rpm the supercharger is constantly activated. The supercharger boost pressure is controlled via the regulating flap control unit."

From Logger's observations this is obviously not the case with the Mk6 TSI engines.

[logger]

..and nor is it for the BLG engine. As I stated "Be interesting to know what the minimum torque requirement to engage the S/Charger below 2400revs is...." If you re read your reference you will see it does not say the SCharger is constantly active below 2400rpm. It says from some nominal "minimum torque requirement" of x & up to 2400rpm it is constantly active. I am wondering what x is.
So when x torque is commanded revs rise quickly to 2400 rpm and SCharger clutch disengages because boost demand is now met by turbo alone. This takes 2-3 seconds. When < x torque is commanded revs rise slowly to 2400 and beyond without SCharger.
If indeed it was constantly active <2400rpm with any torque requirement then whenever you cruise along leasurly at 80kph in top gear on a flat road it would be running. It wont be. Hook your BLG up to VAGCom and you will see what I mean.
What significant differences there are between the BLG and CAV engines? For one the latter has a more modern ECU. Beyond that I dunno.

PS.. mine has the squeal these days and it does not bother me a bit.

[MariusGT]

Logger--

your detail of the engagement of s/c below 2400rpms is exactly what my understanding was.

However I am sure I read somewhere that the s/c can be active ABOVE that 2400 threshold when required.

Does this mean both s/c AND turbo are cranking together at some
points? What would that (y torque value?) requirement be??

OR- gear selected (in manual mode or 6m) is too high for the turbo to
cope by itself so the s/c gives a helping hand?

[logger]

Logger--

your detail of the engagement of s/c below 2400rpms is exactly what my understanding was.

However I am sure I read somewhere that the s/c can be active ABOVE that 2400 threshold when required.

Yes you are quite correct. It can run above 2400 and up to 3500 which corresponds with the SChargers rev limit of 17,500 rpm. My reference to the 2400 was simply to clarify a misconception about when it runs in this band.

Does this mean both s/c AND turbo are cranking together at some
points? What would that (y torque value?) requirement be??

YES. The Turbo will always be spinning while exhaust is passing through its turbine however it needs certain amount of exhaust pressure to produce boost. Supercharger meets this brief gap by rapidly coming online, boosting the engine which in turn boosts the turbo which takes over from the supercharger. Thereby significantly reducing boost lag and allowing for boost at much lower revs than the turbo could achieve.

OR- gear selected (in manual mode or 6m) is too high for the turbo to
cope by itself so the s/c gives a helping hand?

Yeah I expect it would run in a tall gear when there is a high torque demand. Not sure what the actual torque figure is though and it will only be an arbitrary ECU torque in any case. This y value would probably be a curve.

[kriss60]

Just been advised by VW here in the UK that a resolution has now been found to the squeal problem. They have advised me to contact my local dealer asap who will fit new parts under warrenty - Did'nt say what parts but will find out tomorrow when I book the car in.