Clutch Slipping? Golf IV TDI 90 PS Fix!

Hello everyone,

My Golf IV TDI with 90 horsepower now has 120,000 km, and I've decided to get it tuned.
Since the 'Chip on Board' modification, the clutch starts to slip in the higher gears, specifically from around 4th gear onwards. When accelerating at full throttle and around 2500 RPM, the clutch slips. This causes the engine RPM to suddenly increase. When I then release the accelerator, the RPM drops back to the previous level.
I've read quite a bit about this in the forum, but some things are still unclear to me.

Warum rutscht die Kupplung denn nur in den höheren Gängen und gerade bei der Drehzahl durch, in den unteren Gängen wird doch viel mehr Kraft übertragen?? Oder not?

'For me, the biggest power boost is between 1800 and 2400 RPM, but the clutch, if it really is a clutch, only starts to slip afterwards.'

I'm not sure what to do now. Should I replace the clutch? Or could it be that some oil is getting onto the clutch, causing it to slip, but why only in the higher gears?

You can see that I'm, so to speak, Rudi at a loss, and I hope someone can help me!

See you later...
mima

Hello Rudi,

The situation is very clear: your clutch cannot handle the torque produced with the chip installed.
The effect occurs at higher gears because, at high gears, the torque cannot be reduced. In lower gears, the car accelerates or the tires lose traction, so the clutch doesn't experience as much torque difference. In a higher gear, the tires don't slip and the car accelerates more smoothly, but in this case, the clutch has to handle the full engine torque and starts to slip.

'How much did you have the engine tuned? My A3 with 90 horsepower handles the tuned 265 Nm torque without any problems. Of course, it's possible that your clutch is already worn and maybe even slightly oily.'

You can try the 'wood splitter' method: put the car in neutral, depress the clutch pedal, and when the clutch bell opens, spray brake cleaner inside. This might help clean it with minimal effort. If you replace the clutch, consider using a reinforced racing clutch; that should solve the problem.

Hello Joe,

Thank you for the answer!

After 120,000 km, the clutch might be starting to wear out, or maybe not?
My car should now have approximately 260 Nm of torque and 118 horsepower.

Where can I get a high-performance racing clutch?
Can I simply exchange it, and will it fit, or are there other things I need to consider?

Okay, first I'm going to try the 'brute force' method. It's possible that some seal is broken and oil is leaking onto the clutch!

Questions upon questions...!
Sure, here is the translation of the text from German to English:

'so long'
mima

@Joe

I think the thing about the torque might not be entirely correct.
The engine's torque is, of course, the same in all gears.
The transmission only changes the torque at the wheel.
It doesn't matter whether the tires are spinning or not:
The motor delivers power P, which is calculated as P = M * n.
This is then translated into: friction, tire warming , work against the air (air resistance), and acceleration performance (P=m*a*r*n).
(n = wheel speed, r = wheel radius, m = mass of the car, a = acceleration)
When you have the accelerator pedal fully pressed, the engine always delivers the same amount of torque (of course, at the same RPM).
Sometimes, the power is converted only into friction and rotational acceleration of the wheel (M=I*alpha), resulting in a burnout. Other times, it's used to accelerate the air (air resistance at Vmax), and otherwise, it's used for air resistance and acceleration of the vehicle.
My explanation for the slipping in the higher gears is that people tend to use full throttle in those gears, which overloads the clutch. When shifting into the lower gears, the high gear ratio still provides relatively good acceleration, so any potential slipping might not be as noticeable.

That's my opinion on the matter. Please correct me if I'm wrong.

Greetings from Austria.
Ruki.

Yes, it's exactly as Joe wrote.

In a low gear, the engine cannot fully transfer its torque to the clutch. Either the tires will spin (and this can happen with significantly smaller torques than the engine's rated torque, thanks to the gearing!), or the vehicle will accelerate without a burnout. However, in that case, I don't need the full engine torque.
Furthermore, the moment of inertia changes drastically depending on the gear, as seen from the engine/clutch.

In high gear, on the other hand, I have the ability to apply the full engine torque to the clutch because the gear ratio isn't sufficient to generate enough torque at the wheels to produce significant wheel slip.

In some applications, the motor torque is even limited in the lower gears to prevent damage to the powertrain. It's quite easy to roughly calculate how many Nm can reach the drive shaft...

CU Gremlin.

@Ruki, of course, the motor produces the same torque regardless of the gear. However, the corresponding counter-torque from the drivetrain must also be present.

It's almost impossible to ride a bicycle while standing up in the lowest gear. However, you can ride while standing up if you shift into the highest gear, as this creates the necessary counter-torque.

I can only explain why the clutch starts to slip at higher RPMs by considering the aerodynamic forces acting against the clutch spring pressure, thereby reducing the clutch's clamping force. Alternatively, it can also be explained by the counter-torque. The higher the speed in 5th gear, the greater the resistance from the wind, which creates a counter-torque through the transmission.

Hello dear Mima,


I have a Golf IV (engine code AXR) that is on its second clutch at 47,000 km!
I work in a VAG (Volkswagen Group) facility in the warehouse, and I also know of colleagues who are experiencing major problems.
'It might have sliding couplings, but I'm hearing that noise for the first time with a 90 horsepower engine. I don't usually have any problems, even without any performance modifications.'
Whether we like it or not, a new one is needed!

It only slips when it's relatively cold outside?

Hello everyone,
Thanks for the contributions.

Okay, now let's talk about you, marc 70. The last time it was around -2 degrees Celsius, and my tuner installed a slightly more powerful version, which caused the clutch to slip constantly in the higher gears. With the smaller version, it has only happened once, but I have to say that I'm also not pushing it as hard and am driving more cautiously now.

We also re-uploaded the original file, and in that case, the clutch didn't slip.
Either I give up the extra power, or I need a new clutch, or not?

Does the clutch from the 110 HP TDI engine also fit my car? Or even the clutch from the 130 or 150 HP PD TDI engines? Can anyone answer this question?

Best regards,

or

Until next time,

or

See you,
mima

The clutch is more likely to slip in higher gears, as the engine's inertia, which absorbs a significant amount of torque during acceleration, is less effective at the same engine speed. It would also slip in a low gear when climbing a very steep hill.

It's also more prone to slipping at lower temperatures, as the torque is higher in those conditions (a phenomenon sometimes referred to as "summer sag").

@mima

It's exactly as you described it yourself. You can either revert to the standard performance or replace the clutch, and I would recommend the latter. It's already quite worn, and it's not going to last forever. While you might have peace of mind for now, you'll likely regret it later if you eventually have to replace it anyway.

I had the same problem, had an original clutch installed, and now everything is fine. I would advise against a racing clutch, as these don't engage as smoothly as the standard ones. Perhaps a stronger clutch from the Audi range would be a suitable alternative.

Best regards,
Uwe.

@ mima

I'm experiencing the same problem with my ALH, and I've also considered using a clutch from a more powerful TDI engine.
The thing is, the clutches for the 90, 100, and 110 horsepower TDI engines are the same.
Unfortunately, the clutch from the 130 and 150 HP TDI engines doesn't fit because the hub profile is different. This is because both engines have a 6-speed gearbox.

Best regards,
Light switch.

@Light switch

When will you invite me for a test drive?

Perhaps the ones from the more powerful 5-speed PDs would fit?

Currently, I have around 300 Nm of torque in my 110 HP AHF engine, and the clutch is holding up! The first clutch I had also couldn't handle the chip. There are either changes in the production process or significant variations in the manufacturing quality.

Best regards,
Uwe

I just checked with Audi. The 130 hp PD engine has a 5-speed gearbox, but the hub profile doesn't fit either.

Best regards,
Light switch.

Hello,

I inquired with companies like VW, and they suggested that the dual-mass flywheel might need to be replaced.
Is that even possible? Did you actually change that or not?

Best regards,
mima[/img][/list][/quote]

hello mima

Once, the pressure plate and friction disc were replaced, while another time, only the friction disc was replaced. According to the part number, no modified parts are being used. The defect has not occurred again for the last 2000 km!

You could also install an original clutch for your 90hp TDI engine, as the teeth will then fit properly.

Then, simply place a stronger pressure plate on top of the existing one, ensuring it has the same height. You won't need a new flywheel in that case.

You could also contact Sachs directly; they can definitely tell you which one is the right one.

I will not do anything differently in 2 months either, even if my AFN has 180 hp and 380 Nm.