Golf GT SPORT TDi flat spot in third

[Angryman]

Hi all

Did a search but couldn't quite find this exact problem..if it is a problem.

My GT Sport with almost 90000km on the clock has got this monster flat spot btwn 2500-3000rpm in third gear. Especially evident when accelerating out of corners. IT may do it in lower gears as well but its not as evident.

You'll be cranking out of a corner and it'll hit 2500 rpm and then dead like you've just dropped 3 cylinders and then its back on song once the needle hits 3000. Is this a common thing with the vehicle or something I should get looked at.

To put things in perspective I had the ecu replaced at 20000 km after it shagged out on me and wouldn't let me do more than 60kp/h. And its only been the last 6 months that I've really noticed it since I am now daily driving up a windy range road. Previously it was all highway k's and I never noticed it

Any feedback appreciated

Should have added that its a manual with no mods

[Transporter]

It looks like VNT vanes seizing (common) or faulty MAF sensor (less common).
Any messages in the MF display, like Error xx. ?
The first step would be, someone with VCDS or similar to read ECU. Is it still under the warranty?

[Greg Roles]

Yep sounds like VNT valves sticking, but weird it's only in third??
At 90k you'd have a stack of soot in the inlet, and I'd highly recommend a flush at VW. Also, if it's still in warranty, time to visit the local cairns dealer to get that flat spot checked out. I'm in Cairns early Sept for a case at the Private, I'm there all day and can bring up my VagCom cable if need be. Let me know if you need to go down that path.

[Angryman]

Thanks lads,

Yep still under warranty I'll book it in tomorrow for them to look at it next week..... I'll also try and replicate the problem in the other gears

[Angryman]

Right..so some feedback

Got the beastie back from its 90 thou service yesterday and nothing....no error cods, everthing is clean. Service suggested that perhaps its an electrical fault or perhaps something called a soft code that clears out of memory if it doesn't ocur again for so many starts. Was advised to bring it straight in if possible next time it happens....

[PhilVW]

I have seen faults like this before.

Check for software updates - main dealer only, (its like updating your computer online) new 'software' is downloaded into the ECU and that can sort out lots of glitches.

By any chance is this a 3 door TDI Sport? UK import?

Phil.

[Angryman]

Nah, I bought it brand new from Austrel VW in Brisbane in 2007. 5 door GT Sport

[Greg Roles]

What about intake sludge buildup and a sticky EGR flap / valve?

Perhaps look into the threads where people have sprayed the Wynn cleaner stuff into the intake and flushed the massive buildup that occurs out? I wouldn't do it with a DPF car I was going to keep, but as you're going to the dark ( fun ) side soon....

[Angryman]

What about intake sludge buildup and a sticky EGR flap / valve?

Perhaps look into the threads where people have sprayed the Wynn cleaner stuff into the intake and flushed the massive buildup that occurs out? I wouldn't do it with a DPF car I was going to keep, but as you're going to the dark ( fun ) side soon....

As an update the car broke down on Thursday in the middle of central Queensland. Started of as being unable to hold power in sixth and eventually conked out completely. On trying to restart it came up with the check engine light and a message on the MFD saying to take to service centre immediately. Unfortunately I had no mobile phone reception and was 150km from the nearest town so I let it sit for twenty minutes and tried firing it up but it kept conking out.

I then restarted and gave it a hit on the accelerator and it roared to life. It then went into limp mode for the next 250km back to camp. Towed by VW on Friday and now they tell me that they've conducted diagnostics and that they have sent the information to VAG to interpret???? This doesn't sound good.....

[gldgti]

maybe it ate the turbocharger compressor...