A4 TDI AFN: Performance Questions & Tuning (Kassel/Göttingen)

Hello YOU fellow TDI enthusiasts ,

I have an Audi A4 TDI, manufactured in 1996, with the AFN engine and 110 horsepower. The mileage is 107,000 km.


Picked it up from the workshop yesterday... Brake discs completely replaced, ball joints on the front, 1 brake caliper bracket at the rear, brake hoses on the front... €950... Motorcycle vacation postponed for now... .

I found this forum quite interesting!
To avoid having to worry again about the 'big' and expensive TDI engine failing, I have a few questions...

1.) I'm from the Kassel-Göttingen area... maybe some of you are also 'freaks' (enthusiasts)? I would like to have a discussion and possibly arrange a viewing of my car. I will then pay for any drinks afterwards, if desired.

2.) I also have that noise when the window is open on the passenger side, but it might just be the normal turbocharger whistling... maybe?!

3.) A thin film of oil is also present on the connection hoses of the low-temperature coolant system, directly at the coolant connections.

4.) Until yesterday, the vehicle had a tuning module installed. Ulf's test at 2000-4000 rpm showed a time of 6.4 seconds. Without the module, the time is now 7.3 seconds. The car has a total weight of 1315 kg, plus an additional 90 kg with me inside .

I had personally adjusted the module...the car had a real KICK!
Now, I want to be cautious... it's quite an expensive affair if something 'fails.' Then the question arises whether a highly bred diesel engine of today's generation can really be called 'economical' when various components frequently break down (even without tuning!)... then my 'economic plan' is thrown out the window . Riding motorcycles is already expensive enough !!!

5.) When DISCONNECTING the EGR valve, is a noticeable reduction in fuel consumption observed? Does this reduce engine power?

'...those were just a few questions from an enthusiastic A4 TDI driver... yesterday, someone was trying to sell me a new Golf 4 with all the extras and a 75 horsepower gasoline engine... no way... I'm not giving up my blue 'heating oil Ferrari' anytime soon... although VW currently has some good deals...'


I'm eagerly awaiting responses.
I would appreciate any positive feedback.

PS: When I'm riding my scooter, I always think it's an OVER-TDI... with great acceleration .

Regards,
Carsten.

Hi Carsten!

The thing about exhaust gas recirculation and fuel savings sounds very appealing, I've read about it too. I wouldn't say there's any performance loss! As Ulf describes, the whole system only serves to 'shift pollutants' due to the lower combustion chamber temperature in partial load conditions. Nothing more, nothing less.
And because burnt air isn't as verschandeln as 'fresh' air, it produces more smoke.
and we already have enough Russians, or not?

From what I understand, this is better for the engine because of the deposits and such. I can imagine that it could be especially unhealthy for engines that have been chipped/tuned.

and those few NOx emissions will probably be tolerable.
I'm going to try disabling the vacuum hose tomorrow. Nothing much can probably happen.

and the performance certainly doesn't decrease because the entire system only operates in the partial load range anyway. So, at full throttle, it's basically out of operation .

Best regards, Thomas.