Performance loss - can errors be identified in the log?

Hello again,

After having managed to get the performance up to 105 horsepower through chipping, I recently logged some data again, and according to the drag time calculator, my time has increased from 8.02 seconds to 9.5 seconds. That leaves you with only 92 horsepower.
I logged everything to try and find the error. While doing that, I noticed that no values changed, except for the data from the "Boost Valve." In all other logs, these values were always between 50 and, at the end, more than 90. Here, they remain stuck at 66. Could a defect in this valve be a clue? - And what would the target data look like?

Roadrunner505 wrote:

I logged everything to try and find the error. While doing that, I noticed that no values changed, except for the data from the "Boost Valve." In all other logs, these values were always between 50 and, at the end, more than 90. Here, they remain stuck at 66. Could a defect in this valve be a clue? - and what would the target data look like?

Assuming a good match between the target pressure and the actual pressure (deviation = 10 mbar), the duty cycle is perfectly acceptable.

What seems strange to me is the low soot limit (group 8, right column) despite the almost maximum LMM value.
This log looks like the turbidity correction curve wasn't changed (or was changed incorrectly) at all... that would be a case of amateurish tuning.

Do you know this article: /viewtopic.php?t=3101?
In the 1Z engine, the turbocharger boost pressure is regulated using a pressure relief valve. This creates a certain degree of self-regulation (increasing load causes the pressure chamber to be activated further), so it is quite possible that the duty cycle hardly changes.

This value does not allow us to conclude that there is a faulty valve. This is an initial value of the control unit, not a measured value.

I don't have LDA, so I guess I'll have to start the search all over again...

Roadrunner505 wrote:

I don't have LDA, so I probably have to start the search all over again from the beginning...

You probably don't need it, I've rephrased my answer!

Quote:

to start the search all over again...

Then start searching meaningfully, like I and others have often told you!

If you're still not sure whether the problem is caused by the chip tuning or something else, it would be best to put the original chips back in and then create some logs.
It still puzzles me why the smoke limiter is activating even though the boost pressure and air mass are correct.

If I were you, I would log "Gr10" instead of "Gr3". Then you'll also have the value from the ambient pressure sensor.

@ulf:
There's a very long backstory to this case. If you have time, you should read them to stay informed.

@wolfi_b:

Thank you for the note regarding "Back to the roots" - but I've actually already done that. The following log was generated by an engine control unit 028 906 021 B that was used last week. Hmm, well... the boost pressure is already deviating slightly from the target values in the middle... but otherwise...

That's probably just a normal overshoot.

And what about the performance?

Okay, so when I enter the data with the measured times into Rainer's dyno software, it gives me a result of 87.5 horsepower. But of course, I will repeat the entire process today, in case anything has changed since last week.

wolfi_b wrote:

@ulf: There's a very long backstory to this case. If you have time, you should read them to stay informed.

I just checked it again... ultimately, it always depends on the soot limit, which must not exceed 40 mg.

If even multiple tuners can't achieve it, then some other parameter or setting will likely reach its limit at 40 mg, but that limit won't be detected by the tuner.
-> Does it come from the factory with any unusual MSG (or exotic software) that puts tuners at such a disadvantage?

Or, all of his previous tuners follow the (questionable) concept of determining the amount of boost based on the soot limit, rather than the torque limit, as is done in the standard configuration.

Now he could still...

a) Specifically address his tuners, only adjusting the turbulence-based feedback (KF) to increase lift at high air mass over the ailerons, and leaving the rest of the settings as they are.

b) Check with other tuners to see if they can resolve the issue.

c) Obtain a more common MSG (if his is an exotic one) and give it to his tuners.

d) Try it with a 10c tuning, but make sure to have the option to revert to the original software.


Let's see how it goes from here...

@ulf

Thank you for the advice. I've actually acquired another TCU (Transmission Control Unit) in the meantime. Tomorrow, I have another appointment at OBD-Tuning in Harburg. They seem to be very accommodating and will exchange the chip in my AT TCU for one that's compatible with my B TCU. Therefore, I can use the Digitec chip to check the plausibility of the AT control unit, and the OBD chip to check the plausibility of the B unit, against each other.

Maybe something will catch my eye then.

To everyone I seem to be bothering with my problems:

Guys, I've been dealing with these problems for 9 months now.

I visited three Volkswagen workshops, was in contact with both chip tuners for weeks, had the car inspected by one tuner for a day, acquired a second engine control unit and a second tuning chip, and bought a new mass airflow sensor, along with a diagnostic cable and a laptop, specifically for that purpose.

Please stop complaining when I occasionally share new insights or findings related to this topic. I can only rely on hints and insights I've gained myself, and I'm trying my best!

Roadrunner505 wrote:

@I've actually gotten another ECU (Engine Control Unit) in the meantime. Tomorrow, I have another appointment at OBD-Tuning in Harburg. They seem to be very accommodating and will exchange the chip for my AT (Automatic Transmission) control unit for one that's compatible with my B (presumably referring to a different system or component) control unit. Therefore, I can then use the Digitec chip in the AT control unit and the OBD chip in the B unit to cross-check each other for plausibility...

Try to get some information about soot limits.

-> at 850 mg of air.

-> at maximum air volume (how many milligrams of air is that?)?

If it's currently only releasing about 40 mg of diesel at 850 mg, and the system isn't even factoring in higher air masses, then we have a problem...

Ulf.

But how does ******** manage to increase the power of the 1Z engine to 115 hp / 250 Nm?

According to a (simple) proportional calculation, this is approximately 45 mg of diesel.

Does anyone have a ********-chipped or *** (112 HP) 1Z engine that I could read comparison data from?

If you are collecting, I can let mine be test-chipped .

m;

As I mentioned, I'll be able to get the software on a floppy disk soon. However, I won't be able to interpret the data. Perhaps I can send them to someone who is more knowledgeable about that.

dieselmartin wrote:

but how does ******** then get the 1Z engine to produce 115 hp / 250 Nm ??? According to (a simple) proportional calculation, it is approximately 45 mg of diesel.

If the measurement system can only account for a maximum of 850 mg of air, in the opacity measurement process, you would release, for example, 48 mg of diesel into the air at 850 mg and set the torque value to 45 mg.

However, in a driver-demand system, the pedal travel of 100% still requires a minimum of 45 mg of torque.

Sure, Ulf.

It seems that the master tuners that Road had previously consulted were not able to do it.

m;