Strange Behaviour

[pinkgti]

Hi I'm a newbie but have been looking at these forums for a while.

I had my Mk6 GTI tuned recently and it's not exactly behaving itself.

Anyway thought I'd post some pics of some logs and see if anyone has any idea whether it's a problem with the tune or hardware.

First one's shows the actual boost vs requested boost @ full throttle 2nd gear



Second is moderate acceleration with fixed throttle position running with DSG in "D". Short-shift in 1st, 2nd gear to 3,000RPM and then cruising. Note that the boost drops off after 2,000RPM which results in loss of power.



Anyway interested in your thoughts and yes I will be going back to the tuner but want my ducks in a row first.

[h100vw]

You need to do logs in 3rd, you get a much better idea of what's happening. What do you mean by not behaving itself?

Back to the tuner is the way to go. Boost leaks are not uncommon.

Gavin

[pinkgti]

You need to do logs in 3rd, you get a much better idea of what's happening.

Thanks Gavin. OK 3rd gear but then I'll have to wait until I can find a nice bit of highway (110km/hr) zone to try that out

What do you mean by not behaving itself?

Boost comes on way too late - 3,500RPM. I would have thought that the requested and actual boost would have followed each other a lot more closely until the K03 runs out of puff.

Back to the tuner is the way to go. Boost leaks are not uncommon.

Yep just thought that I'm eventually getting boost that maybe it's something else.

Thanks for your suggestions.

[h100vw]

Thanks Gavin. OK 3rd gear but then I'll have to wait until I can find a nice bit of highway (110km/hr) zone to try that out



Boost comes on way too late - 3,500RPM. I would have thought that the requested and actual boost would have followed each other a lot more closely until the K03 runs out of puff.



Yep just thought that I'm eventually getting boost that maybe it's something else.

Thanks for your suggestions.

You'll get a better look at the boost on a 3rd gear pull. A rip up to 5000 would probably give enough info, it's going to die off any way but assuming your tune is from a known source, they won't be requesting more boost than the turbo can make low down. Otherwise you could spend a lifetime chasing non-existent leaks.

As a mild comparison my Polo makes full boost by 2800 and the S3 by about 3200.

Gavin

[pinkgti]

You'll get a better look at the boost on a 3rd gear pull. A rip up to 5000 would probably give enough info, it's going to die off any way but assuming your tune is from a known source, they won't be requesting more boost than the turbo can make low down. Otherwise you could spend a lifetime chasing non-existent leaks.

As a mild comparison my Polo makes full boost by 2800 and the S3 by about 3200.

Gavin

Yeah not too concerned about the 5,000-6,000 at the moment - mainly bottom end as that's what I use 99% of the time anyway.

The other thing is under moderate accelerate the power delivery isn't smooth - kind of surges. Between 2,000-3,000RPM is a flat spot.

So do you think it might be a problem with the turbo if it's not spooling up fast enough? Or maybe just a stuffed up tune.

[gldgti]

I would check with the tuner ASAP, but if it was a hardware problem it could be an exhaust leak between turbo and engine (manifold somewhere) or perhaps the wastegate is not closing properly.

Antoher thing to consider might be foreign object damage of the turbocharger compressor wheel.

[parso_rex]

Does the ECU have to come out of the car each time ?

[pinkgti]

Does the ECU have to come out of the car each time ?

In my particular case it is due to Bosch encryption. I believe this may not necessarily be the case will all Mk6 GTI's though.

It must have been that they added encryption with the pink paint option or something.

[parso_rex]

They aren't encrypted.
They may be doing it this way (via BDM) to apply their own OBDII read blocking though, some places here do this.

In my particular case it is due to Bosch encryption. I believe this may not necessarily be the case will all Mk6 GTI's though.

It must have been that they added encryption with the pink paint option or something.

[Guy_H]

Who is the tuner? as above with Parso, no MK6 GTI that is delivered in AU needs the ECU pulled out, and blocking the OBD stops VW putting any updates on the car.