TSI recall?

[SGGT]

Same issues I had with the 24M3 software which I posted in:

http://www.vwwatercooled.org.au/newforum/upload/showthread.php?t=13187&page=3

[ts1eepa]

Got my recall notice in the mail yesterday, but yet to take it into the dealer.
It got me thinking about the change to the boost gauge behaviour others are experiencing with 24M3 applied.

Firstly, I doubt the VW engineers would do anything by accident since any software update would need to be tested extensively.
Secondly, since owning the car, I have found the boost gauge a lot more 'sensitive' than in other turbo cars I've driven.

Without any numbers on the gauge or some other way of reading the boost this is only a theory but here goes:

I reckon that VW have now recalibrated the gauge so that it only displays a reading once the boost pressure is positive. Most aftermarket gauges show vacuum (negative) pressure up until about halfway on the gauge and usually require a reasonable amount of throttle to move the needle past 'zero'. I think up till now, the gauge in the TSI has been showing vacuum pressure all the way up to almost 2/3 of the gauge. This change makes sense if you think about it since there are no numbers or units and one must assume that the zero point on the TSI gauge is on the far left

I'll have more confidence in this theory once I see the needle deflecting for myself after I get the update..

[LiFers]

I reckon that VW have now recalibrated the gauge so that it only displays a reading once the boost pressure is positive. Most aftermarket gauges show vacuum (negative) pressure up until about halfway on the gauge and usually require a reasonable amount of throttle to move the needle past 'zero'. I think up till now, the gauge in the TSI has been showing vacuum pressure all the way up to almost 2/3 of the gauge.

I dissagree.

Most after market guages are measuring a Turbo car, boost is built up progressively from 1800rpm and onwards. Below that there is either very little boost, or there is a vacuume (naturally aspirated).

A TSI would have boost from the supercharger just off idle, being that that's what it's designed for. There would be almost no periods where the engine is operating in a vacuume.

[ts1eepa]

I agree with you, the supercharger in the TSI starts producing boost from pretty much just above idle. As to whether this boost is actually positive pressure - it's hard to say for sure until someone hooks up a real gauge to measure it.

I do notice from experience in driving the TSI and listening to the whirring going on in the engine bay, the turbo/supercharger combo seems to spool up around 2/3 mark with the 'old' gauge. I admit I'm not an expert with forced induction, but it has a similar feel to the 'zero' point on a turbocharger regardless of engine speed. This could be just the turbo starting to kick in and the supercharger is already working its ar$e off, who knows...

I also think there has to be a logical reason why VW would change it! They wouldn't just bust it right?!?

Any TSI owners with an aftermarket gauge able to share their experience?

[BarneyBoy]

The supercharger cuts off at 3500 rpm.
The turbo starts to spool up at 2500 rpm.
The 2500 -3500 range is the so-called 'hand over' period that the TSI does so seamlessly.

IMO, this is also the 'funnest' time in a TSI!

[LiFers]

I also think there has to be a logical reason why VW would change it! They wouldn't just bust it right?!?

Having done a lot of database testing you'd be surprised what bugs make it through test regimes only to result in an "oh no!" moment after it has been put into production.

(Not on my watch though! Well ok, not often.)

This one does sound pretty stupid to not be intentional or the unavoidable by product of a different change.

[warhead]

Car has just been through a checkup after the 24M3 upgrade and logging of the fault with the boost gauge not being responsive whatsoever.

Well my dealer just called me and said they did all the tests volkswagen asked them to do and compared with another TSI with the 24M3 (they don't have one that hasn't been through the upgrade... I find that a bit hard to believe, a demo TSI from early MY08 shouldn't have the upgrade unless they went ahead and updated all their cars).

Turns out there's nothing mechanical or electrically wrong with the car, it definately has something to do with the update.
The dealer also claims they don't know what the update actually does, they only know as much as was revealed in the recall notice and that the changes are confidential information to VW.

Well, it's my car and I feel I have the right to know what happened and why my boost gauge is like how it is now. Personally I don't care. But if I'm to resell this car a few months down the track, I'm almost 100% sure the buyer will say there's a boost gauge (wow cool!) but it doesn't work at all in the exception is when you're driving like you're fleeing from a crime scene.

I believe because of this the car actually loses some of it's value (not a lot, but some), some people will think less of it because the gauge there does nothing. I'd (they'd) probably rather have the temperature gauge there instead.

What do you guys think?

[POLARBEAR666]

My cars gearchange pattern in D has improved since the update. It holds gears longer and the supercharger does not surge in and out anymore. It just feels like its there constantly.

My fuel economy has improved too so I think there are some changes to shift pattern and supercharger function also.

Very happy.

[warhead]

My cars gearchange pattern in D has improved since the update. It holds gears longer and the supercharger does not surge in and out anymore. It just feels like its there constantly.

My fuel economy has improved too so I think there are some changes to shift pattern and supercharger function also.

Very happy.

Fuel economy improvements might be related to any changes they made to the DSG functions (although I didn't think this would be part of the ECU) as I drive a manual and I've noticed no changes in fuel consumption.

[tdi guy]

what letter?

I bought my TSI in May, and have not been contacted about the update. However, I was asked to bring the car into the dealer (McCarrolls) in September 'to upload warranty details to the VW worldwide computer system', so perhaps this was just a 'ruse' to cover for the update...

[tinto]

Perhaps, but the only way to know is to plug in a diagnostic cable (like a VCDS) and see what version of the software is on your car.

Depending on your build date, you may already have it from the factory.