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Audi A4 2.0 2005 - Poor running, with black smoke - Fixed #

Posted by Ian Waring on January 5, 2012, 11:20 pm

Year of Manufacture *: 2005
Engine Size and Code *: 2 Ltr 2di

Engine fails to rev, with black smoke from exhaust.

If boost pressure hose to wastegate diaphram is removed, engine will rev but with no turbo. With engine running there seems to be too much vacuum to wastegate diaphram.

Have checked wastegate actuator arm and diaphram - all working. Also stripped E.G.R Valve, cleaned and rebuilt. Fitted new boost pressure solonoid but fault remains.

Audi dealer tells me this particular model is riddled with engine problems. Main problem is I have no data for testing sensors.

Have not worked on too many diesel faults - anybody give me any pointers to work with?

Re: Audi A4 / Poor Running, with black smoke

Posted by Mark Carter <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1428' width='330' height='300' border=0 style='border:none;'> on January 6, 2012, 12:14 am, in reply to "Audi A4 / Poor Running, with black smoke"
Mark Carter

Hi Ian,

>>> Have not worked on too many diesel faults - anybody give me any pointers to work with? <<<

Black smoke is either, overfuelling OR under airing.

>>> Have checked waste gate actuator arm and diaphragm <<<

As far as I know this vehicle does not have a "waste gate" as such, have a quick read up on how the system works and it may help you with the vacuum readings you are seeing.

What is live data telling you?

Any fault codes?

Regards Mark

Modern cars, Its all wizardry and witchcraft

Re: Audi A4 / Poor Running, with black smoke

Posted by Ian Waring <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT5344' width='330' height='300' border=0 style='border:none;'> on January 6, 2012, 1:02 am, in reply to "Re: Audi A4 / Poor Running, with black smoke"

Yes, understand your comment re. wastegate - is controlled by ECU.

Any links to reading up on how system works?

Have Autodiagnos but not able to use live data on VW Audi.

No fault codes to hand.

Cheers for reply, Ian

Re: Audi A4 / Poor Running, with black smoke

Posted by Mark Carter <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1428' width='330' height='300' border=0 style='border:none;'> on January 6, 2012, 7:42 am, in reply to "Re: Audi A4 / Poor Running, with black smoke"
Mark Carter

With regard to the links,You could do worse than google VAG SSP

The vehicle does not have a "Waste gate" as such.

Look up VGT Turbo control.

There will be loads of Info on the system. Hth

Mark

Modern cars, Its all wizardry and witchcraft

Re: Audi A4 / Poor Running, with black smoke

Posted by Lee Mackintosh <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1348' width='330' height='300' border=0 style='border:none;'> on January 6, 2012, 8:15 am, in reply to "Re: Audi A4 / Poor Running, with black smoke"
Lee Mackintosh

Why wont your Autodiagnos let you view any live data, when i used to own it i'm fairly certain it did.

Infact i think it was fairly good with VAG models. If i remember correctly you select what engine code version you have then all the data is then in sections depending on what you want to look up.

Fuel system
Turbo system

Re: Audi A4 / Poor Running, with black smoke

Posted by Chris Angus <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT5111' width='330' height='300' border=0 style='border:none;'> on January 6, 2012, 11:54 am, in reply to "Audi A4 / Poor Running, with black smoke"

Have you checked for boost leaks, I see this problem quite a lot with various cars, turbo can still maintane pressure but overspeeds and maf reading is higher resulting in more fuel being injected.
Sometimes disconecting the maf will make it run better as it will default to a basic fuel map.

Chris

Re: Audi A4 / Poor Running, with black smoke

Posted by Ian Waring <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT5344' width='330' height='300' border=0 style='border:none;'> on January 8, 2012, 6:44 pm, in reply to "Re: Audi A4 / Poor Running, with black smoke"

Thanks again for all help.

Am going to speak to Area Rep re. Autodiagnos as I can only get block data to appear.

Customer has taken car and will rebook. Have now got some data (many thanks to Dave) so working on that, in conjunction with google search suggested.

Will report back. Cheers everyone for help.

Re: Audi A4 2.0 2005 - Poor Running, with black smoke #

Posted by george rayner <iframe src='https://members.boardhost.com/ukautotalk8/info/user=UKAT1272' width='330' height='300' border=0 style='border:none;'> on January 11, 2012, 8:02 pm, in reply to "Audi A4 2.0 2005 - Poor Running, with black smoke #"
George Rayner

check that it is not sucking hoses in,if it is,remove exhaust and look at turbo spindle,they collapse and jam up,if you are getting boost,"hoses pressurize on rev up" you may have a split intercooler pipe.if you have a smoke machine you can fill system with this to find leaks.

Fixed #

Posted by Ian Waring on January 21, 2012, 10:47 pm, in reply to "Re: Audi A4 2.0 2005 - Poor Running, with black smoke #"
Message modified by board administrator January 23, 2012, 11:27 am

Autodiagnos confirmed will read live data on early vehicles ... however it will only read block data on later vehicles.

Thanks for everyones input - EGR Valve faulty.

Have gained valueable technical info on this system in the process.

Cheers
Ian

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