Technical Clutch and brake pedal knock/vibration

[Evodepevo]

Can someone help me? I recently bought a 1.4 Punto Evo Dynamic and something doesn't sit well with me.

When at idle you can feel a slight knock in both the clutch and brake pedal. It's a slow knock that disappears when you put your foot lightly on the clutch paddles free play. When you put both feet on brake and clutch paddle (free play point) it disappears in both pedals.

On the highway it's also felt en the vibration is much faster when putting your foot lightly on the clutch.

Anyone any ideas? I was thinking maybe a servo, engine mount or master cylinder problem?

 

[J4MALD1N]

I had a similar issue on a different vehicle (a Merc Sprinter). Any vibration in the clutch pedal would radiate and be felt in the brake pedal as they’re usually part of one unit with the exception of the gas pedal. The clutch bearing had severely failed in that van and the clutch pedal would vibrate unless the pedal was pushed to the floor.

Back to your Fiat,
Are there any noises alongside the vibration? (Video would be helpful)
Are there any issues with shifting or any clutch wear symptoms?

The most likely cause of this is something to do with the clutch. It could be something like a worn release bearing or damaged clutch components. I’d also check to make sure nothing is coming into contact with the clutch lines, master cylinder etc. Any vibrations from the engine can radiate through the lines and be felt in the pedals.

All the best!

 

[Evodepevo]

I had a similar issue on a different vehicle (a Merc Sprinter). Any vibration in the clutch pedal would radiate and be felt in the brake pedal as they’re usually part of one unit with the exception of the gas pedal. The clutch bearing had severely failed in that van and the clutch pedal would vibrate unless the pedal was pushed to the floor.

Back to your Fiat,
Are there any noises alongside the vibration? (Video would be helpful)
Are there any issues with shifting or any clutch wear symptoms?

The most likely cause of this is something to do with the clutch. It could be something like a worn release bearing or damaged clutch components. I’d also check to make sure nothing is coming into contact with the clutch lines, master cylinder etc. Any vibrations from the engine can radiate through the lines and be felt in the pedals.

All the best!

Hi J4MALD1N, thanks for your help.
There are no noises alongside it from the engine bay.the knock feels very mechanical and when you hold your foot lightly on the clutch (neutral) and increase the rpm it goes away, only to come back again around 600rpm at iddle.(or when your moving and lightly touch the clutch you will also feel lots of vibration in the free play area of the clutch pedal).

Car shifts like butter and the clutch does not slip. It also doesn't sit very high (the pedal does feel springy in my opinion compared to my last car but that one didn't have a hydraulic clutch).

When you depress the clutch you can hear a small whine like noise from the engine bay while moving, but that's about it.

 

[J4MALD1N]

Hmm. That whine sound could be a clutch bearing. Maybe check the pedal box itself and make sure everything down there is nice and tight. May also be helpful to check all the gearbox and engine mounts since they could be your issue. Unlikely these are the cause since the entire car would shake however it is worthwhile a check.

It's hard for me to exactly determine the issue without actually driving the car however from what you've mentioned, seems like a clutch bearing issue but could be any other component such as flywheel, clutch plates etc. Do you know if the car has had any clutch work done? What's the mileage?

 

[Evodepevo]

Hmm. That whine sound could be a clutch bearing. Maybe check the pedal box itself and make sure everything down there is nice and tight. May also be helpful to check all the gearbox and engine mounts since they could be your issue. Unlikely these are the cause since the entire car would shake however it is worthwhile a check.

It's hard for me to exactly determine the issue without actually driving the car however from what you've mentioned, seems like a clutch bearing issue but could be any other component such as flywheel, clutch plates etc. Do you know if the car has had any clutch work done? What's the mileage?

The car has done 162.000 km. No mention of any clutch work done, lots of things have been changed thru the years but no invoice that mentions the clutch.

 

[J4MALD1N]

That may be the issue. A lot of garages sometimes replace clutches but not the bearing. I had a MK2 Punto that got a new clutch however a few months later the bearing began to misbehave. At that mileage it is possible that your car still has the original clutch. If you start to hear any sort of abnormal noises when pressing the clutch then the bearing is definitely the issue.

 

[Evodepevo]

That may be the issue. A lot of garages sometimes replace clutches but not the bearing. I had a MK2 Punto that got a new clutch however a few months later the bearing began to misbehave. At that mileage it is possible that your car still has the original clutch. If you start to hear any sort of abnormal noises when pressing the clutch then the bearing is definitely the issue.

Oke, I will also go to the dealer than. Strangely no noise when I press the clutch just the pulsing/vibration at the clutch and brake pedals highest point. I also read somewhere something can be resting against the hydraulic master cylinder so will check that out to as the intake seems to be very close to the hydraulic lines. Thanks for your help.

 

[J4MALD1N]

That’s true yep, check everything you can.

All the best!