Tuning: 10 Cent Fix, 170 km/h Power Loss?

hello everyone...

I once tried the 10-cent tuning method. The resistance is approximately 700 ohms. When I turn it on while driving, you can notice a slight difference, but I'm not sure if it's really that impressive. However, if I do it on the highway and turn it on at around 130 km/h and then accelerate, it seems to cause a slight jolt and a complete loss of power at around 170-180 km/h, and the car only goes up to about 120 km/h. Turning off the tuning immediately doesn't help; you have to turn the engine off and restart it. However, I haven't seen any error messages, so I assume the resistance isn't too low. There are no issues at idle, except for a minimal increase in the idle speed.

'I once measured the time from 50 to 100 km/h in 3rd gear. In its original condition, it took 7 seconds. With a 10-cent tuning, it took 6.3 seconds. Is that a normal time? A speed calculator suggests a time of 6.9 seconds without tuning, so I think that's okay. However, I can't say anything about the time with the tuning.'

The car is a Golf III TDI with 110 horsepower, manufactured in 1996, engine code AFN. The weight... I'm not sure, but I think it's around 1250 kg.
Okay... tire size is 16 inches with 205/45.

Okay, here's the translation:

'Also, if I engage it at around 180 km/h, there's a slight acceleration... but it only lasts for about 5 seconds... because then what I described above happens.'

Is a 10-cent tuning not suitable for high RPMs?

Your engine control unit is going into emergency mode, and your description fits perfectly... you've gone too far with the tuning. Instead of a resistor, why not use a potentiometer or a trimmer? That way, you can find the optimal value by adjusting it.

Best regards,

Jan.

Hi.

Based on my own experiences with VTG (Variable Turbine Geometry) issues, I can definitely imagine that if the fuel injection quantity is increased, the turbocharger's boost pressure may no longer be regulated correctly, which could then trigger a limp-home mode.

Do you have a boost gauge installed?
If not, I strongly advise you to get one of those parts, because the charger seems to cause problems frequently with the AFN, and it allows you to quickly check if the pressure is normal or not.

Hello,

I connected approximately 850 ohms in parallel between pin 2 and 3. This resulted in a significantly better performance and torque. Now, it reaches a top speed of 195-200 km/h and accelerates quickly to that speed. Before the tuning, it barely reached 175-180 km/h.
The vehicle doesn't produce any smoke. However, when I reach the maximum speed, it goes into limp mode after a while and only runs at 120-130 km/h. But if I drive at a maximum speed of around 170 km/h, regardless of how long, everything seems to be fine.

(My vehicle: VW Passat TDI, 90 horsepower, year of manufacture: 1999)

Who can help me with that?

Best regards,