Audi A3 1.9tdi limp mode at high revs

[Ch4ndler]

Bought from a garage and the problem started happening just after 3 months of owning the car (about a week after the warranty ran out - sods law). In 1st, 2nd and 3rd gear the car pulls just fine, every now and then I get a little stutter, like I have taken my foot off the accelerator and put it back on quickly. If I hit a duel carriageway/motorway and floor it after changing to 4th, it will go into limp mode around 65mph. If I change to 5th gear at 2500 revs (55-60mph, to prevent the limp mode in 4th) and floor it in 5th, as soon as it gets near 70mph it will go into limp mode. I currently get round this problem by bouncing the accelerator in 4th and 5th.

I'm was fairly sure it was sticky vanes so took it to a vag specialist garage who charged me £120 for clean the turbo out with chemicals (probably the £50 kit from eBay plus labour). Tested the car after I picked it up and the problem went away, a week later and the problem returned, £120 down the drain.

Now for the flaming.

I changed the air filter to a K&N. Pointless on a diesel I know.

I installed a chip from tdi-tuning. Cost me £120. I was happy to pay more than the cheap chinese ones from eBay as I believe they cause more harm than good. With the chip on or off the car has the same limp mode problem.

Unsure whether these points are relevant but it always helps to know the history.

Car has 105000 miles on the clock.

Where do I go from here?

 

[SAiLO]

Scan it with VCDS to confirm if you have any codes related to sticking turbo vanes problem (Overboost codes).
Apparently best fix is to either strip the turbo and then clean it or replace it with a new/refurbished unit.

I'd go back to the garage who charged £120 and complain that the issue returned within a week.

 

[NHN]

The turbo cleaner is temporary at best & if its a VNT unit, then it needs removing & cleaning properly or it will just come back time & time again & eventually blow up.

Scan the car & show us the logs 1st, probably show us overboost errors.

Also, fitting a tuning tool when you have engine limp issues is not a good idea, fix the problem 1st before buying tuning mods & the K&N is pointless, its a 1.9TDI, it wont make any difference imho.

 

[@udi A3]

3 months warranty means nothing when your consumer rights allow 6 months from time of sale to challenge the cars condition. remove the mods and return it for them to inspect and fix under the sale of goods act.