Braking system

Tach schön. Mal eine Frage an die Bremsenspeziallisten. Mein Audi A3 MJ 1997 (ich weis, ist nen altes Auto ) hat folgendes Problem. Wenn ich mittelstark bremse, dann kommt kurz das ABS und danach ist eine spürbar geringere Bremsleistung zu spüren --> stärkerer Druck auf das Bremspedal --> Vollbremsung, welche aber auch nicht ganz überzeugen mag. Meine Bremsanlage ist neu mit Flüssigkeit befüllt und entlüftet worden, die Beläge vorn sind zur Powerdisk passend (beides ATE), welche aber ihr letztes Lebensviertel erreicht hat. Hinten Standartbeläge und Scheiben von Audi (ebenfalls letztes Lebensviertel). Den Eindruck der Bremsleistung hat sie aber schon eher erweckt, nicht erst jetzt, also, denke ich, liegt es nicht am erhöhten Verschleiß. DeI'm sorry, I can't translate that because it appears to be incomplete or nonsensical. Please provide a complete and coherent German text for me to translate into English.The brake hose to the power brake booster is okay. The braking force is "excellent," according to ADAC after the brake test. The ABS control unit has no errors, and EBV (Electronic Brakeforce Distribution) is also working correctly. Could there be a problem with the master cylinder? Or could it simply be due to the age of the vehicle? Thanks!

@davidshoes:

Quote:

When I brake moderately, the ABS activates briefly, and then a noticeably reduced braking force is felt.

What do you mean by that? Do you brake so hard that the braking system enters its normal operating range and then remains there until the brakes are fully released or until the vehicle comes to a complete stop, or does most of the braking process occur outside of the normal operating range?

In the first case, i.e., within the normal operating range, it is perfectly normal, especially on dry roads, for the deceleration within that range to be lower than during braking. The maximum deceleration occurs at the beginning, until the wheels start to lock up. Then, the ABS system adjusts the wheels to the point just before locking, which slightly reduces the deceleration in favor of the vehicle's maneuverability.
Interessant wäre vielleicht auch noch zu erfahren, aus welcher Geschwindigkeit Du bei Deinen Tests abgebremst hast, welche Bereifung Du fährst und wie der Fahrbahnzustand war. Auch der Stoßdämpferzustand könnte von Bedeutung sein, da wenig effektive Stoßdämpfer nämlich auch den Bremsweg erheblich verlängern! {MARKERBitte gib mir den deutschen Text, den du übersetzt haben möchtest.

I think that with these additions, the professionals here in the forum will be able to help you much more quickly.

Regards,
Alex.

Okay, it almost doesn't matter what speed you're going. I brake outside the normal range, but sometimes a manhole cover or something similar will cause the ABS to briefly engage. I know how all that works – ABS, ESP, etc. In the past, the deceleration would remain relatively constant with the same pedal pressure. It would just momentarily adjust itself and then return to the original deceleration rate. The road surface is dry, and I'm using Dunlop SP Sport 9000 tires in size 205/55 ZR 16W on 7.7-inch alloy wheels. The shock absorbers aren't in the best condition anymore; they have over 122,000 kilometers (approximately 76,000 miles) on them. I'll be replacing them soon. But even with that, I'm surprised by the different braking behavior.

Nach Deiner Beschreibung tippe ich auf ziemlich ausgelutschte Stoßdämpfer. Deinem Fahrwerk genügt schon der kleinste Störeinfluss, wie z.B. ein Gullideckel oder eine Querfuge, um die Radaufhängung in eine völlig unzureichend gedämpfte Schwingung zu versetzen.
Due to the vertical movement of the wheels, the contact force on the ground periodically decreases and increases, causing the ABS system to intervene constantly during the unloading phases. When the suspension rebounds, each wheel then leaves the control range again as the contact force increases.
"Could you please do a shock absorber test? I bet that's the solution to your problem! I don't know how the experts here in the forum see it, but I think my interpretation fits your description of the issue."

Regards,
Alex.

donalexo wrote:

Could you please do a shock absorber test? I bet that's the solution to your problem! I don't know how the professionals here in this forum see it, but I think my interpretation fits your description of the problem.

Hi,

That sounds logical. However, 122,000 km is not excessive mileage . If you're not constantly driving on cobblestones, the shock absorbers should still be in good condition. Our Audi 80 TDI with 270,000 km had over 70% remaining during the test (initial shock absorbers ), which means they were still okay .

@haehnlein:

Quote:

klingt logisch. 122.000 km sind jedoch keine übermäßige Laufleistung Wenn Du nicht dauerhaft Kopfsteinpflaster fährst, sollten die Stoßdämpfer noch i.O. sein.

The mileage as a wear indicator for shock absorbers is not very informative. I once experienced this with a company car (Opel Astra) where the shock absorbers were completely worn out after only 50,000 kilometers. The daily driving distance consisted mainly of country roads and highways, and the vehicle's load was also within the normal range!
The driver's driving style, however, was somewhat notorious !

What I mean to say is: It's best to take a test and then decide!

Regards,
Alex.

klingt logisch. 122.000 km sind jedoch keine übermäßige Laufleistung Wenn Du nicht dauerhaft Kopfsteinpflaster fährst, sollten die Stoßdämpfer noch i.O. sein. Unser Audi 80 TDI mit 270.000 km hatte beim Test (erste Dämpfer ) noch über 70%->i.O.


Okay, here's the translation:

'My record is burning through a set of brake pads in 30,000 km.'

Distance is not an indicator in this case.
The ABS problem, however, seems to me to originate from this direction. In the past few weeks, I have often had vehicles of more recent production years in front of me on the 'test track.' What the rear wheels were doing in some cases was frightening .

Similarly, my colleague's company car. It's not even two years old, has 80,000 kilometers on the odometer, and is in such terrible condition that I almost got thrown out of it...

-> Test bench rules.

CU Gremlin.

"Thank you for your opinions. I was actually planning to have different dampers installed anyway. Now it looks like I'll go with the Bilstein B6 Sport ones. I want something good quality, but the springs are still in good condition and the car definitely shouldn't be lowered! From my experience in cycling, I know how valuable a good damper is. I'll let you know if it also improves the braking."

Hi,

If you are a member of the ADAC or a similar organization, you can have the shock absorbers checked for free .