What happened to my AFN 1.9TDI?

krook

Veteran Member
Joined
Jan 13, 2021
Location
Hungary
TDI
A4 B5 AWX, A4 B5 AFN
Hey!

I have recently bought a 1997 Audi A4B5 with an AFN engine. When I bought the car, the turbo was not working, and it was getting limp-mode fairly often so I tried everything I could find on this forum, and finally traced it back to a broken vacuum line. After I replaced it, the turbo started working again and it felt like I was in an other car, the car performed very well. I looked at VAG-COM to check the boost pressure and it seemed health, the actual value seemed to follow the required value, maxing out at approximately 2000 mBar (so the actual boost maximum was roughly 1 bar plus the atmospheric pressure), I suspect that is the default on engines. However, the engine stopped on the way home and could not be started again. It was recently taken apart and we could see that cylinder 2 has melted. I'm getting the engine replaced with another AFN, but I'm curious what may have I done wrong and what to look out for when the new engine is installed so this does not happen again. I'm perfectly fine with the stock performance of the engine, currently not looking to do any mods to it, be it software or hardware.




Any help is appreciated! Thank you.
 

Mozambiquer

Vendor , w/Business number
Joined
Mar 21, 2015
Location
Versailles Missouri
TDI
2004 VW Touareg V10 TDI, 2012 Audi Q7 V6 TDI, 1998 VW Jetta TDI. 1982 VW Rabbit pickup, 2001 VW Jetta TDI, 2005 VW Passat wagon TDI X3, 2001 VW golf TDI, 1980 VW rabbit pickup,
My guess would be injector failure. That's what it looks like to me.
 

pedroYUL

Veteran Member
Joined
Sep 8, 2011
Location
MI, USA
TDI
2015 Passat CVCA; 2015 GSW CRUA; 2012 wagon CJAA; 2004 wagon BEW
I think that was prior damage. Now, the piston looks like a valve was dropped, but then the head is something else. Probably Mozambiquer is right.
 

krook

Veteran Member
Joined
Jan 13, 2021
Location
Hungary
TDI
A4 B5 AWX, A4 B5 AFN
I think that was prior damage. Now, the piston looks like a valve was dropped, but then the head is something else. Probably Mozambiquer is right.
Thank you! I do not know how long the previous owner used it without the turbo, so it has probably not died on him only because the lack of boost.
 

MATPOC

Veteran Member
Joined
Dec 28, 2020
Location
Providence, near Hope
TDI
2003 Jetta Wagon 5-speed
Looks like foreign object damage, something fell inside.
Bring that #2 to tdc and collect all the pieces, something might still be in there that does not belong..
 
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