10cent tuning?

Hello everyone.

I modified my Galaxy with what is called a '10cent tuning.'
Now I've noticed that when I fully accelerate in 4th or 5th gear, I hear a strange whistling or hissing sound from the engine, as if the turbocharger's wastegate is constantly opening and closing.
It can be heard approximately every 2 seconds, and lasts for about 1 second. It's not as noticeable in the lower floors.
If I turn off the tuning, it's immediately over.

If I'm lucky and can access the OBD with VAG-Com, and then check the boost pressure, I notice the same thing... it's between 1790 and 2050, and it's constantly fluctuating up and down.

Could it be that I've cranked up the settings too much?
Or does anyone know what that could be?


Best regards, Mike.

I once tried something similar with my 1Z. I noticed that it mainly accelerates in a jerky or uneven way in 3rd gear. Imagine it like this: thrust, pause, thrust, pause, thrust...
Basically, it has good power delivery, but then you notice it starts to lag, and then you feel the power kick in again. This happens within the RPM range of 2400-4000. So, you don't really lose power between these power surges, but you definitely feel noticeable jerks in the acceleration.
The time I measured in the Ulf test was 6.3 seconds.
I suspect the cause is simply a setting that is too high.

Hello, can anyone tell me how the permeability test is performed? I've found the test to download, but I can't open it.

Best regards,

wacken wrote:

Hello, can anyone tell me how the pull test is performed? I've found the test to download, but I can't open it. Regards

I'm sorry, but I cannot access external websites or specific files online. Therefore, I am unable to translate the text from the provided URL.

The ventilation calculator is an Excel file, but it can also be used with StarOffice (StarCalc).

Best regards, Rainer.

Rainer K. wrote:

...But it also works with StarOffice (StarCalc).

OpenOffice also works!!

I'm having trouble getting them to turn on, but I did manage to take a measurement, and it was 5.85 seconds. What does that mean?

Best regards,

it takes you 5.85 seconds to go from 2000 to 4000 RPM.
You can compare this value with other cars, which will show you where you stand in terms of performance.

But let's get back to my question: why is the power delivery so jerky, especially in third gear, and not as smooth as with the standard power output?
The potentiometer has already been turned back, so it doesn't seem to be a power issue.

x world one wrote:

But let's get back to my question: why is the power delivery so jerky, especially in 3rd gear, and not smooth like with the standard power output? The potentiometer has already been turned back, so it doesn't seem to be related to the power output.

Hi,

Without more specific information (LDA values??), I'm initially attributing it to an overload of the charger control system due to the increased exhaust flow, which is manifesting as symptoms similar to a limp mode.

If there is no defect in the magnetic valve, the charging mechanism, etc., it might be possible to resolve the issue by adjusting the VTG or wastegate threaded rod – by turning it in the direction of "less boost pressure."

Okay, thanks. I'll wait until the LDA is installed and then I'll specify the problem in more detail.

ulf wrote:

x world one wrote: But let's get back to my question: why is the power delivery so jerky, especially in 3rd gear, and not smooth like with the standard power output? The potentiometer has already been turned back, so it doesn't seem to be related to the power output. Hi, Without more specific information (LDA values??), I'm initially attributing it to an overload of the charger control system due to the increased exhaust flow, which is manifesting as symptoms similar to a limp mode.

Hello Ulf,

Finally, I have an LDA in my Golf.
That's why I can finally make a statement about it.
I've noticed something regarding the LDA (likely referring to a specific technology or process) when it comes to serial performance:
1. Significant overboost, full throttle in 2nd gear at approximately 30 km/h, and the LDA (likely a pressure sensor) shows approximately 1.3 bar. If you continue to accelerate, it slowly returns to 0.9 bar.
2. In 3rd gear, the boost reaches up to 1.1 bar; in 1st gear, when starting with full throttle, it even reaches 1.4 bar.
"On a flat road in 3rd gear at approximately 2000 RPM, the boost pressure is just below 0.2 bar. When encountering a slight incline, the boost pressure increases if you try to maintain 2000 RPM."

The latter is normal, although 0.2 bar seems low to me. But the overshoots are quite significant, aren't they?

With a 10-cent tuning adjustment, the LDA fluctuates between 0.7 bar and 1.3/1.4 bar, and quite rapidly. This would suggest increased exhaust flow and an overload of the control system. However, I don't think the increase is that extreme. Based on your dynamometer test, I calculated approximately 109 horsepower and 249 Nm of torque.

So, just adjust the wastegate?

Hi,

We've already discussed the overboost events. You can see them quite well on an unregulated LDA (Lambda Dynamic Air Mass sensor), and especially more clearly than you can via VAGCOM.

I don't think that's bad at all. I've also seen readings as high as 1.3xxx bar on the digital display of my ASV (which doesn't have any needle lag), when I've really pushed it. What's more important is that the whole system settles down quickly, and that's what's happening with yours – reaching those 0.9 bar (or 1 bar in my case).

Best regards,

Jan.

Thanks, Jan. Yes, the Überschwinger have already been discussed. But to me, it seems like a bit too much, especially considering the serial production.

What do you mean by "quickly reaching operating pressure"? Because it stays at 1.3 bar for quite a while. When I give it full throttle at around 30 km/h in second gear, I have to rev the engine for it to reach operating pressure. Once it does, I almost have to shift gears again. So, it noticeably stays at 1.3 bar. It's not like the gauge goes to 1.3 bar and then immediately drops back down.

I believe my VDO display has a built-in damping feature.

That looks like a stuck wastegate, doesn't it?

joergs wrote:

That looks like a stuck wastegate, doesn't it?

Yep, I suspect that too - assuming the hoses and the solenoid valve are okay.

Hi,

Quote:

What do you mean by "quickly reaching operating pressure"? Because the pressure stays at 1.3 bar for quite a while.

Okay, that's definitely too long. Your text made it sound like they are only short, and that the 0.9 value will quickly adjust during further acceleration. Of course, they shouldn't stay at a fixed value for too long.

Therefore, please check what Jörg and Ulf wrote.

Best regards,

Jan.

First of all, thank you all.
The good wastegate... could it be that you can't even reach it on a 1Z engine?
I will check the solenoid valve tomorrow. Unfortunately, my measuring device is malfunctioning when checking the resistance and is only giving me error readings, so I will need to get a different one tomorrow.

The hoses leading to the solenoid valve, one red and one blue, appear to be intact until just before the valve itself. There, they seem to be rubbing against the air filter housing. It's obviously difficult to see if there are any leaks in those areas. I'm going to try sealing those spots with electrical tape to see if it makes a difference.
But as I said, I don't know how to access the wastegate. It's located pretty far down at the back of the engine, making it very difficult to reach.

Edit:
I just took it for a short test drive. The noticeable oversteering is still there, especially in the first and second gears. However, it's now returning to center faster than yesterday. I've now taped up one of the two hoses that were previously clamped, the red one. So, it seems that it's probably leaking.