TSI squeal noise problem on acceleration

[Golf Mark 6]

Well I went to the dealership and drove around the block with one of the service guys. He pretty much confirmed what we already know - that it's the magnetic clutch on the water pump.

I asked him if it could cause any damage to the components around it and he responded with a no, it was just a known sound from a TSI engine.

Previously VW had told them to change over the water pump, and this solved the issue for a few weeks but then the sound came back. At the moment VW has told dealerships to leave it, but he believes that a solution to the sound could be coming soon from Germany.

Personally, I'm happy that the dealership at least knows the reason for the sound. Given the age of the car, I'm pretty confident my warranty will cover the change-over on the new clutch when it eventually gets here. Don't want to attempt any change if VW has advised against it.

[logger]

...I think my unburnt fuel issue is due to the magnetic clutch not engaging properly & taking it's time to overcome the springs that disconnect the clutch.

I would have thought the clutch would $h1t itself pretty quickly if it slipped for several seconds every time it was engaged. If it really is doing that, you might be in need of a new magnetic clutch sooner than you think. Even if this is what is happening, as there are two intake pressure sensors at separate points downstream of the supercharger wouldn't the correct amount of fuel be scheduled for the achieved pressure in any case? Or is fuel metered to scheduled press as against achieved pressure? Perhaps the cause is totally unrelated to the supercharger and its magnetic clutch.

[Tommy]

I would have thought the clutch would $h1t itself pretty quickly if it slipped for several seconds every time it was engaged. If it really is doing that, you might be in need of a new magnetic clutch sooner than you think. Even if this is what is happening, as there are two intake pressure sensors at separate points downstream of the supercharger wouldn't the correct amount of fuel be scheduled for the achieved pressure in any case? Or is fuel metered to scheduled press as against achieved pressure? Perhaps the cause is totally unrelated to the supercharger and its magnetic clutch.

Howdy

yep, that's what i reckon too. if you've got metal parts making noises like that, there's got to be wear and tear...and what other damage is being done?

sounds like you're a big rig driver... kenworth?

[VW Convert]

Howdy

yep, that's what i reckon too. if you've got metal parts making noises like that, there's got to be wear and tear...and what other damage is being done?

sounds like you're a big rig driver... kenworth?

81,000KW 1,000 L/100km, can't be a truck, it's something much bigger, a boat or an aircraft?

I think this issue is being handled badly by VW in terms of communication but I'm equally certain they are working on and will come up with a solution which will end up with a recall at some stage in the near future. It is likely that they have a policy of saying nothing until a solution is found for legal reasons and dealers are not in a position to make commitments on behalf of the manufacturer.

Part of my job is administration of warranty claims to a major company that manufactures cars, trucks and materials handling equipment amongst other things. From experience I can say that it takes time to identify the nature and scope of the problem, develop and most importantly test a solution, manufacture the parts required, distribute the parts worldwide and contact each individual owner to arrange rectification. Patience is the key here, VW won't walk away from its obligations, they can't afford to and the law won't allow them to.

Cheers

George

[Tommy]

Freight train?

[cktsi]

I would have thought the clutch would $h1t itself pretty quickly if it slipped for several seconds every time it was engaged. If it really is doing that, you might be in need of a new magnetic clutch sooner than you think. Even if this is what is happening, as there are two intake pressure sensors at separate points downstream of the supercharger wouldn't the correct amount of fuel be scheduled for the achieved pressure in any case? Or is fuel metered to scheduled press as against achieved pressure? Perhaps the cause is totally unrelated to the supercharger and its magnetic clutch.

It's not happening all the time... still only around 2% of the time (though it hasn't occurred for 2 weeks now fingers crossed). All I know is 3 weeks ago it happened 3 times in 1 week and the squeak is getting slightly fainter... so I was wondering if there is a correlation.

It's possible the unburnt fuel is unrelated to the magnetic supercharger clutch. I don't know the mechanical setup of the exhaust & how it interacts with the fuel injection - so you could be correct that it's still an unrelated issue. I just made the connection based on my on suspicion + polarbear's internet find.

I thought it may be the supercharger as everything else is mechnically fine. The only way I could rationalise it is that there's lots of unburnt fuel which suggests that there isn't enough air in the mixture i.e. when the engine is under load, the fuel injector is responding with more fuel, but the supercharger isn't forcing in the corresponding amount of air... upshot is I still get acceleration, but lots of unburnt fuel spewing out back.

Like you, I thought it could be something else. I enquired about whether a sensor may be faulty, but the head mechanic said that the sensors were all fine. In the end, we're all really in the dark about the root cause.

[logger]

...sounds like you're a big rig driver... kenworth?

81,000KW 1,000 L/100km, can't be a truck, it's something much bigger, a boat or an aircraft?

Yeah VW Convert you're on the money.

It's not happening all the time...
..It's possible the unburnt fuel is unrelated to the magnetic supercharger clutch. ...
I thought it may be the supercharger as everything else is mechnically fine...... upshot is I still get acceleration, but lots of unburnt fuel spewing out back.... In the end, we're all really in the dark about the root cause.

Lets hope they find a fix for you soon. Tried to hobble my Supercharger clutch today to see if I could create a plume - but no luck. Temporarily disabled my Aux Coolant Pump instead. woops.

[cktsi]

Temporarily disabled my Aux Coolant Pump instead. woops.

Woah... are you saying you are using Vagcom to change certain configuration to try to replicate the issue? Wow.. that sounds very high tech & impressive. How do you know what to manipulate & what the values are?

[logger]

Nah nothing as clever as that. Just using Vag-Com to verify I had disabled the correct sensor by physically disconnecting it, which it told me I had not. Was after G582 which is a current sensor. BTW I did get a bit of a plume out the back this arvo, but it was only cos I was giving it too much of a bootful when it was still cold and had only been running for about a minute....

[cktsi]

Nah nothing as clever as that. Just using Vag-Com to verify I had disabled the correct sensor by physically disconnecting it, which it told me I had not. Was after G582 which is a current sensor. BTW I did get a bit of a plume out the back this arvo, but it was only cos I was giving it too much of a bootful when it was still cold and had only been running for about a minute....

So if you have a Vag-com (or access to one), have you tried other "hidden" settings? I read the thread in the Mk5 forum about the rain sensor being able to close windows & sunroof when it detects water (provided the wiper stalk is in the rain sensor mode position). Ever tried something like that one?