The idea won't let me go: Steam engine on a V6 TDI

I once owned a BMW Alpina B10 Biturbo (and the fuel was still affordable back then). It had a steam gauge in the center console, and if needed, you could temporarily increase the boost and unleash enormous power, which was absolutely 'hellish.'
Okay, here's the translation:

'Now I have an A6 V6 TDI, and I've been having some problems lately (which I've posted about here). Now the turbo, various seals, hoses, and filters are new, and an idea won't leave me alone: As far as I know, the car has an external sensor for the boost pressure in the intake manifold. This sensor is located at the front, bottom left of the intercooler (or?), and has two cables. If I now disconnect the cable to the control unit and connect it to a potentiometer, I should be able to trick the control unit into thinking there's too little boost pressure by providing a lower voltage (adjustable), and it would then compensate (increase) accordingly. Am I mistaken, or should this work?' Okay, I need the data from those of you who are knowledgeable: what voltage does the control unit report when there is 0 bar of boost pressure, and what voltage is reported at approximately 1 bar of overboost? Also, I'd like an electrician among you to tell me what range of resistance (in ohms) I would need to make adjustable in order to, for example, increase the boost pressure from 0 to 0.3 bar, depending on the position of the steam valve... Oh, and I'm driving with a faulty EGR system and a PBOX, so I have enough diesel available to increase the boost pressure. Sure, here's the translation:

'Thank you in advance!!!'

'If I now disconnect the cable to the control unit and connect it to a potentiometer, I should be able to provide the control unit with too little boost pressure by reducing the voltage (which can be adjusted), and it would then try to compensate.'

Or the engine control unit detects the artificially reduced intake air pressure, reduces the fuel supply, and enters a limp-home mode. I think Audi is more likely to go in that direction. He checks how high the turbo is running using the variable geometry turbine (VTG), notices that something isn't right, and adjusts the settings to prevent the turbo from overboosting.

Personally, I don't think you have much of a chance; I believe something needs to be programmed in the engine management system. Still, it's an interesting thing to be able to briefly unleash maximum power.


Regards,

Sebs.

bdsf2003 wrote:

If I now disconnect the cable to the control unit and connect it to a potentiometer, I should provide the control unit with too little boost pressure due to a lower voltage (adjustable), and it would correct (increase) it, right?

Yes... but why?
If you expect more performance from it:
Okay, I'm ready. Please provide the German text you want me to translate.

Hello bdsf2003,

Raising the voltage isn't a major problem. You just need a diode with a low forward voltage drop. This is connected in series with the output line. Behind the diode, on the line leading to the steering device, you need a resistor to increase the current flowing through the diode, which will reduce the voltage drop across the diode.

The resistance could potentially be adjusted (within limits). I adjusted it myself and gained about 0.2 bar. However, a mechanical boost pressure gauge is needed as a reference for testing.

The search function returns a lot of information, especially about the V6 engine.


How about you? I also have a P-box, and I find the Russt to be too loud in the lower RPM range. I would have liked to have had the boost pressure increased here, but below 1700 RPM, the pressure builds up too slowly.


Good luck with your crafting!

Rainer.