Lambda Sensor Tuning: Improve Fuel Efficiency for $0.10

Hello to all the professionals in this forum!

I know a few people who have had their TDI engines tuned.
I've tested something like that before, too.
'In the process, I noticed that under certain circumstances...'
(Humidity? Temperature?) more benefits.
Sometimes, but often quite a bit.

Gasoline engines typically use a lambda sensor in the exhaust pipe.
to measure the excess air in the exhaust gases.

Wouldn't it be a good idea to install such a sensor in a TDI engine?
to be upgraded, and (e.g., via a FET) to adjust the resistance value.
to adjust the tuning so that a certain level of...
What percentage of oxygen remains?

Then, one would have...
1. hardly any Russian.
2. Optimal consumption values.
and
3. Nevertheless, always aim for the maximum possible performance.

What do you think of this idea?

presumably, the probe would become contaminated...

Sounds good so far.
The most current diesel engines now all have a lambda sensor, so I wonder if the manufacturers had already considered something like that?

Look here:

http://www.oeamtc.at/netautor/pages/resshp/anwendg/1098379.html

or here.

http://www.wz-newsline.de/seschat4/200/sro.php?redid=58576

@bafische:

Do you happen to know which manufacturers already use wideband lambda sensors for diesel engines, and if so, in which engines (is VAG also among them)?

Thank you for your responses!

Unfortunately, they raise even more questions.
The articles are beautifully and elaborately written.
Unfortunately, they don't provide any real facts.

What exactly is meant by the term 'broadband probe'?

Could you, for example, use a lambda sensor from a gasoline-powered car?
for my purpose?


Sigi.

ampac wrote:

Look here: http://www.oeamtc.at/netautor/pages/resshp/anwendg/1098379.html or here. http://www.wz-newsline.de/seschat4/200/sro.php?redid=58576 @bafische: Do you happen to know which manufacturers already use wideband lambda sensors for diesel engines, and if so, in which engines (is VAG also among them)?

At VAG, the 3.0L V6 TDI engine uses a wideband oxygen sensor from Bosch, which I believe is the LSU-4. The 4.0L V8 engine should also have one (or two, of course), but I'm not entirely sure.
Otherwise, almost every other manufacturer now includes a lambda sensor with their new EU4 compliant and catalytic converter systems, typically from Bosch or Delphi.

Lambda probes detect Lambda 1 and do so very accurately. The output signal is almost a step function, around which the engine control unit (ECU) oscillates as long as the engine is operating within the Lambda 1 range (this is often no longer the case above 140 km/h in gasoline engines, at which point the mixture is significantly enriched).

This is not suitable for diesel engines, which always have residual oxygen in the exhaust and therefore never reach a Lambda value of 1. Now, analog sensors have been developed for the new direct injection (DI) gasoline engines. These sensors can detect residual oxygen over a wide range and output an analog signal corresponding to the amount of O2. Up to four of these sensors, which cost between 500 and 700 euros each, are installed in the DI gasoline engines. Anyone who gets lead or other contaminants in their fuel will have to cancel their next vacation.

Back to diesel: It's possible, there are engines that run on it, and it doesn't produce excessive soot, but it's not a good solution for DIY projects because you would have to assume that a certain oxygen content always marks the soot limit, which is not the case. However, if you leave a higher percentage of O2 to prevent soot, it can also work without a sensor.

From my perspective: Having slightly more boost pressure than necessary can reduce soot and exhaust gas temperature.

Point 1 and 2 of your approach are correct.
Regarding point 3: If there is still residual oxygen in the exhaust, it means that a small amount of diesel may still be unburned, which implies that more power could potentially be achieved. The optimal performance is not being reached, and therefore, power is being wasted.
I'm increasing the boost pressure and cooling the intake air to get more oxygen into the combustion chamber, but then leaving some of it unused?

Due to the combustion characteristics of a diesel engine (referring here to pre-chamber engines, although it might be similar in direct injection engines), the maximum power is achieved with a slightly rich fuel mixture, meaning there is a slight excess of diesel fuel. However, this is undesirable and not efficient.

Okay, so point 3 is being questioned. But it's good for the environment... therefore, a good approach.