Audi A4 3.0 TDI: Top Speed Limiter?

Hello everyone, I hope you can help me.

I drive an A4 Avant (manufactured in 10/2005) with a manual transmission and a 3.0 TDI engine, originally with 204 horsepower. So far, after a long run-in period, the car has reached approximately 245 km/h according to the speedometer, and it wouldn't go any faster.

Now I've had the car chipped to 252 horsepower. It runs excellently and has power in every situation. It's enormously powerful; it accelerates like it's been stung . It's especially enjoyable that the car now delivers significantly more power above 3500 RPM, unlike before when it felt restricted and powerless.

However, the top speed remains just under 250 km/h according to the speedometer. While it now reaches this speed much faster and is intended to go even faster, the officially registered top speed has increased by 12 km/h. Based on how it feels, it should now easily reach a speedometer reading of 260-265 km/h. However, something is limiting its performance. At just under 250 km/h on the speedometer, the car slightly jerks, stops accelerating, and doesn't go any faster. It's like "brief acceleration, then no more acceleration," and it's similar to the 250 km/h speed limiter found in some high-performance cars. In 6th gear, the engine speed is just under 4200 RPM, while the redline begins at approximately 4600 RPM.

I had the error memory checked, but no errors were found.

Does anyone recognize this behavior, or have any idea what might be causing it? I would appreciate any tips and information you can provide.

I suspect that you need to have the speed limit removed .

Regards,
Maxx.

Thank you for the suggestion, but that's not the issue. Firstly, a speed limit would only apply at 250 km/h, not at 250 km/h on the speedometer. Secondly, these diesel vehicles do not have a speed limit.

Firstly, a speed limit would only apply at 250 km/h, not at 250 on the speedometer, and secondly, these diesel vehicles do not have a speed limit.

1.) When the speed limit is enforced depends on the speed detected by the MSTG (Mobile Speed Detection System).
This can certainly correspond to the value displayed on the speedometer.

2.) Since the introduction of the EDC15, the functionality of a speed limiter has been included in the...
Tax control units are present. Whether they are active or not, and at what speed, remains to be determined.
The way in which speed limiting is implemented is not uniformly regulated. For example, in the T5, it is active (and also noticeable; I believe the maximum speed was 180 km/h).

Best regards,
Rudi

Okay, that might be true in some cases, but it's not the situation here.

It seems to be related to the engine speed, because the same cars with automatic transmissions have a slightly longer gear ratio and reach a speedometer reading of 260-265 (even at 4,200 RPM).

Apparently, something is being limited or restricted at 4,200 RPM in 6th gear. What could that be, and how can I get rid of it?

How high does the RPM go in the lower gears? Over 4,200?

Yes, in the first 5 gears, I can easily rev up to 4,600 RPM, which is where the redline begins.

"Our A 170 automatic transmission also had a speed limiter at 4200 RPM in the highest gear. It's likely that the car is simply limited by engine speed, not by speed."

It's also possible that it was done as a protective measure for the fuel injection pump, to prevent it from being operated at its limit for extended periods.

If both of you have a limitation that only applies in the highest gear, then I don't understand why you believe it's a speed limit rather than a RPM limit.

To put it directly, if the car is limited to a specific engine speed only in the highest gear, then it will also be limited to a specific speed. This is what is called a speed limiter.

The end.

No, it's not a speed limit. The same car with an automatic transmission actually achieves a good 15 km/h more in top speed - and that's at the same engine RPM.

... and what if these 15 km/h are considered as a tolerance?

Then 6% (for a value of 250) ... could be considered acceptable.

m;

Or the automatic transmission has a longer gear ratio.

Or the automatic transmission has no limit .
As soon as the part number or the coding changes, there are differences!
Since that can happen .

Best regards,
Rudi

Rudi wrote:

For example, in the T5, it is active (and also noticeable; I believe it was 180 km/h)

Sure, here's the translation:

"Minor correction/addition..."

http://jewuwa.de/T5/T5_Sites/T5_Tipps/T5_Sonstiges.htm#Vmax

Sure, here's the translation:

'Minor correction/addition...'

http://jewuwa.de/T5/T5_Sites/T5_Tipps/T5_Sonstiges.htm#Vmax

Hmm... der 2005er AXE mit Schaltgetriebe sollte demnach keinen Begrenzer haben. The one who...
As a rental car, it definitely still had a top speed of approximately 180 km/h .
[Speculative mode]It's possible that Europcar and similar companies are getting 'special editions.'[/Speculative mode]

Best regards,
Rudi

The automatic transmission has a longer gear ratio. As I mentioned, the automatic transmission reaches 4,200 RPM at 265 km/h and then locks out, while with my manual transmission, the same thing happens at 4,200 RPM, but because it has a shorter gear ratio, it only reaches 249 km/h.

Let's go back to the question: The tuner says it's definitely not a speed limiter. That's right, it must be something else, such as a shutdown or limitation of the fuel injection at those specific 4,200 RPM. Has anyone experienced something like this before, or how could one disable it or adjust it?