AFN Operation Without Needle Lift

Hey everyone,

Can the AFN engine be coaxed into producing proper power output in an emergency, even without a signal from the throttle position sensor? I'm not talking about limp-home mode, but full injection. The throttle position sensor signal can't be absolutely essential for survival, since every mechanical TDI engine works without it. If you base it on a standard map, it should be possible to achieve this even without that signal. How could one activate this standard map?

The reason for this question is the operation of a TDI engine far from civilization. Things like EGR and mass airflow sensors are completely unnecessary . I understand that we are moving closer and closer to fully mechanical, "dumb," and "inflexible" injection pumps, but sometimes a working engine is more important than any exhaust emission... While excessive emissions could potentially cause our descendants to die sooner, a malfunctioning engine could lead to fatalities in certain areas. I'd rather be selfish for now .

Regards,
Jens.

You could decouple the NHG from the nozzle 3.

So, we need to build a "device" that provides a comparable signal to nozzle 3, based on the pressure in the pipeline.

You could also fake a signal for appendix G28 (speed), which would output a value that is, for example, always 5 degrees before Top Dead Center (TDC). Or even make it adjustable via a potentiometer, from 15 degrees before TDC to 5 degrees after TDC .

But seriously, what do you do if you burn out a piston in the desert because some desert dweller sold you bad diesel fuel? You're just going to be stuck there.

And at least in emergency mode, you can still get out of the desert.

In a pinch, you could try "brutally" tuning the system to force it into a "failsafe" mode.

The more I think about it, the more it seems like something that could be useful in the wilderness - or maybe just bring a new nozzle along .

m;

Hi Jens,

Basically, you're right, he doesn't need the NBF, but the MSG system prioritizes the signal and inevitably goes into emergency mode. (If it completely fails, and not just occasionally malfunctions).
I'm not aware of a simple workaround. However, he doesn't stop moving; he just moves poorly and stumbles a lot.
To fake this signal, you would need to store the adjustment map in a ROM and feed it to the MSG via a processor.

In other words, if you have any concerns about that, bring a spare nozzle (NBF) with you on your travels. It can then also serve as a backup nozzle.

Hi,

Thank you for your suggestions.
The idea of generating a signal from an NHG (presumably a type of sensor) using a complex electronic circuit is nonsense, especially considering my goal. The motor should be made to run using the simplest possible means, and a complicated component like a fake NHG would be completely counterproductive.
If there's no easy way to circumvent the NHG, then you probably need to have one. It's certainly not terrible, but it would be cheaper the other way around.
I should probably consider getting a second engine control unit and experimenting with the parameter fields. Things like the AGR (selective catalytic reduction) system can be easily deactivated, and I'm sure the NHG (noise-harmonic generator) signal can also be bypassed. This would essentially be the "minimum program," meaning a running TDI engine with only the absolutely essential components .
In the end, there aren't that many components left, and compared to a mechanical diesel engine, you only need the engine control unit itself (with integrated boost pressure measurement), the valve for turbocharger control, the throttle body, the crankshaft speed sensor, and ???.
Does anyone happen to know what's absolutely essential and still needed, so that I can fill in the "???" with the appropriate content?

Regards,
Jens.