Hi guys, newbie here...(I will post in teh newbie section and say hi when I get a mo....)

I've been looking through the posts on here and i'm getting myself a bit confused... heres the problem,

I've got an A3 Tdi sport 8P (53plate with a remap). When im driving along a dual carriage way or motorway and overtake (or just accelerate) the car will all of a sudden lose power, this usually happens at high speed or when im hard on boost (pulling onto/overtaking on the motorway).

If I pull over and switch the ignition off and restart, the car is fine. Its done this several times now and the last time as I pulled away it seemed to hesitate just under 2k and a slight jolt just after...cloud of black smoke and it then felt like it did when I first had the car (it was mapped when I bought it and went from a Mk3 8v golf to the mapped A3, so it felt bloody fast lol) It hasn't cut out since, although ive been driving it mostly under 3k, not good when you want a play though ;o)

Some of the post suggest its the turbo going/on the way out and others point to other things first, boost pipes, intercooler etc. During the service it was pointed out that I had an intercooler seal leaking which is being sorted in the next week or so.

Am I looking at a big bill? Is there other thing I can try?

regards

phatboy.....

First of all mate, welcome! Now it needs a scan with vagcom. But what you are describing is a classic case of an overboosting turbo. You see the variable vanes get clogged and causes the turbo to create too much boost pressure, which the ecu recognizes and then shuts the car down to a limp home mode. The vanes can be cleaned using a product from innotec, and you can manually move the actuator to try and free the vanes, but if the clean doesn't work, it means a turbo recondition or renewal.

Hi Stevee, thanks for the reply

I forgot to say that i've had the fault coedes read and nothing came up (although it wasn't a proper vag-com unit) 

Have you used that innotec stuff? How much is it, gotta be worth a try at least.

if I do go for a replacement is the turbo from the 140bhp engine different to the 170 bhp turbo?

It is a different turbo, I can get you part numbers later, would you know your engine code? It should br a stamp under the boot carpet or on service book cover page. Innotec is very easy to use mate. You dint have to take turbo off either

I wouldnt buy anything until you see what its like when you have fitted new interccoler seals,they always leak a bit but if you have had car mapped what you describe with the smoke etc is common

 i had a similar problem with my old golf and it was one of the boost vacuum pipes! the little thin black pipes controlling the boost pressure! but like said the intercooler seels would probably cause the same.

I can see how a leaky vaccum pipe or faulty n75 could make a overboost, not sure how the intercooler seals would make that happen. If they were gone I'd imagine always low power, plenty of black smoke. Does negtive deviation of boost pressure cause limp mode?

Just read wiki on fault 17694 and negitive deviation can cause limp mode. So, check all boost hoses for leaks, n75 and actuator... And really helpful would be a scan to know why it's limping...

Ps, if it's going like a train after a restart of ignition, and doesn't seem low on power- my moneys on an overboost

On the golf the boost hoses were not sealing so too much air in the mix so the ecu chucks more fuel in and a james bond style smoke screen,best way to tell i have found on other cars is lowish speed 2nd or 3rd gear and nail it loading/pressuring up the system quick and listen out for any louder than normal whistling,obviously dont do this a lot because of strain on everything

 My first port of call would be get the VNT checked out and tested, 9 time out of 10 this wil cure the high load limp mode.

Innotec turbo cleaner is the best solution which I think retails at around £50, or we can carry out the whole cleaning, testing and setup for £90.  Before we carry any work out we will make sure its not summat simple that making the car limp.

 

Nick

 I've got code 11618 Boost Pressure Limit Exceeded (that'll explain the limp mode!!)

Check the n75, vaccum hoses to it, and if that doesn't fix anything, then it will have to be a innotec job.

Just a question.Does this issue bring on a Management light anywhere when it happens or should it?

I too have had this similar fault, but I just thought it was a 'glitch' ? Do I have a pending fault too?

 Have you got it scanned or does it have any particular problem characteristics?

 Very occasionally (Three times) , when putting my foot down to accelerate away from motorway slip roads onto the motorway, I have lost all power and thought it was initially something electrical? Upon stopping and switching off and then back on..all is ok? Took it back to the dealership where we was told it faulty pipework? Not sure having read this issue??

All seems ok but you do feel a little uneasy at times with this! I have n't had it Vag com 'd yet but I feel the need may be sooner !

 

Regards Paul T

 

 Hi Guys,

ive just joined this as im having the same problem, my problem code is 16618 - turbo overboost condition..

im a Virgin with Audi's.. i have an A3 2.0 TDI 140 SLINE 2006 3DOOR

can any1 please recommend me on what i should do and if you know any garaje that deals with Audi/VW in the Northwest Manchester area..???

and another thing, how do i upload a Pic of my car..??

Cheers guys

 

 

 

 

 

 Hi mate. I uploaded from Photo bucket.Its quite simple even for me being 'old'!  Dont know if this is the best to use, but it worked for me. Check out Staffordshire newbie. The photos are of my sons car.

As regards your faults, sounds very similar to mine! I have just put mine in to Audi Stafford to have it checked out. |Got fed up with it!

There seems to be an abundance of knowledge on here so I'm sure the guys will help you out.

Kindest regards Paul T

AhmedA3:

 Hi Guys,

ive just joined this as im having the same problem, my problem code is 16618 - turbo overboost condition..

im a Virgin with Audi's.. i have an A3 2.0 TDI 140 SLINE 2006 3DOOR

can any1 please recommend me on what i should do and if you know any garaje that deals with Audi/VW in the Northwest Manchester area..???

and another thing, how do i upload a Pic of my car..??

Cheers guys

 

 

 

 

 

Welcome to the forum first of all. As with most problems, it's best to get it scanned with vagcom / vcds for fault codes otherwise you can end up replacing things that don't need replacing, i.e. using guesswork. As for nearby garages, there's Awesome GTI, PSI Tuning in Stoke and there's a guy from uk-mkivs.net who has just started a garage business in Royton I think. He's getting good reviews.

 the problem code i got from vagcom was 16618 - turbo overboost condition,

engine management light has also appeard in my dash.

now what can i do to get that repaired..??? or shall i say, whats the main possibilty of the problem?

cheers

Main reason for this is normally because of sticking turbo vanes causing the turbo to create too much boost, which causes the ecu to go into limp mode.

 and whats the best way of getting it sorted..? and is it a huge task and big billed..?

It normally means taking the turbo out and cleaning or as it's out, reconditioning. You can get a turbo cleaner by innotec that you can use without taking the turbo out. But that's if the problem is as I stated...

 i think the innotec sounds good but how do you use that thing and were can i buy it from..?

and yes the problem is exactly what your saying..

 

I think you can buy it in eBay, maybe some motor factors? Not sure mate. It's worth a shot though!

 another question for you guys, where is the N75 valve found..?

i take it to garajes and all they say is change the Turbo..?

 Here is a pic of the turbo with the N75 on top. Have the garage checked that the n75 is working properly or that the vanes move freely inside the turbo?

9 times out of 10 it does mean a new turbo or a refurb one, but you have to do those checks first to make sure.

 

 whats a MAF sensor..?

could this be the concern of the problem..?

 MAF = Mass Air Flow sensor. It relates Air intake density for the Ecu to work out the mixture for the engine. If it goes then the engine will run poor. But id say your problem is still sticking turbo vanes.

is it possible for myself to take the turbo out and clean the vanes and put it back in..? i can do bits and bobs (mechanicly)

or is it best to take it to a garaje.? i need the cheapest options..?

The innotec cleaner is around £50 and yu don't have to take turbo off to clean it. It has a sealer cap to go over the turbo. Garage might not charge too much to do the job, maybe an hrs labour? It's not the hardest of jobs.

I have a 2005 Sportback 2.0 tdi sport and it does this.

The turbo boost pipes blew off four times (AA failed to do a temp repair) and then the ECU light came one - it kicked out loads of black smoke as you'd expect. I actually took it in at MOT stage and complained about this hiccoughing sound, but they couldn't find a fault.

This time it's all gone Pete Tong. The Intercooler is cracked (£615) and they can only diagnose the turbo fault once the intercooler is replaced - or so they say.

I have been driving it in limp mode here and there, but am reluctant to part with a bunch of cash when I have no confidence the Audi dealership will find the fault and fix it.

It p*sses me off that they didn't find a fault and now I'm facing a big bill to replace a part that shouldn't have failed. To top it call they came back with over £600 additional 'problems' - break pads/discs etc which I never went in for. Sometimes I think authorised dealers are no better than sharks with an official badge on.....

 

You can get intercoolers alot cheaper than that mate. Try breakers or even forge motorsport. I can't see why a new cooler and new clips holding the hoses on you shouldn't be back in business

 http://shop.ebay.co.uk/?_from=R40&_trksid=p3907.m570.l1313&_nkw=audi+a3+intercooler&_sacat=See-All-Categories

Hi, I'm new here too, but seem to have the same problem as everyone else. I have already gone down the turbo clean route but it didn't do any good. The car runs fine, but under heavy load the turbo cuts out just like everyone else's. The car logs the over boost error code and occasionally throws the engine management light. Sounds like it's time for a new turbo. I've seen a number on eBay like this one but are there lots of different models? Also, I'm fairly handy with the spanners so I want to have a bash myself. Has anyone written up a how-to anywhere? How tricky is the job? Thanks in advance for any help. Nick

 

 

Overboost might not be the turbo. It could be, but then again it might be the turbo control valve (N75) or the MAP sensor. N75 controls the amount of boost the turbo produces, and MAP (Manifold Absolute Pressure) reads the amount of boost the turbo produces. Before you go throwing a turbo at it, I'd investigate these items first. Much cheaper.

 i have a standard turbo for sale for a bkd engine am just about to take it of mine.

i had it recon 2 years ago by Turbo technics.

is listed on ebay so inbox me if interested.

r.menesse@yahoo.co.uk

As rusty said check the vacuum lines to the n75, but be ready for the money of a turbo because it still might be that

 overboost is normally turbo as far as i can remember.

faulty n75 or vac pipes will cause underboost i was told