Hi,

 

My Fabia 1.4 petrol has always had a vibration to it since I've had it (about a year) as you accelerate through about 2000-2800 rpm (above that it's fine), which vibrates the whole car. Feels like it's got a bit worse recently and also I think there's a rattling sound audible as you slow down to a stop. All feels like it's emanating from the front left. Engine mount? Knackered suspension part? Someone has asked whether I have a dual mass flywheel - do I?

 

Thanks,

Jon

No, normal flywheel.

Is it the same in every gear?

33 minutes ago, sepulchrave said:

Is it the same in every gear?

Hi, yes, it doesn't matter what gear I'm in.

Ok, the only plausible explanation is that something has come adrift in the clutch assembly, the rattling could be the cush springs in the driven plate. Has the car had a new clutch fitted and if you rev the engine gently in neutral while stationary can you feel or hear this vibration?

I couldn't tell you about any change of clutch.  Not in my ownership.  It's a rally and autosolo car that gets some abuse - lots of 1st and 2nd gear racing - so a clutch issue would not be too much of a surprise.

 

Just did a test when stationary.   It's smooth when increasing the revs for idle up through to 3000rpm.  On the road, it will cruise without any vibration as soon as you reach just under 3000, and acceleration over 3000 to the redline is smooth as well.  It's just driving and accelerating through around 2000 (maybe just under) up to nearly 3000 that the car vibrates. 

Edited 10 September, 20205 yr by jonmad

I suspect that the clutch driven plate has died horribly and is now effectively a zombie clutch.

The only way to be sure is to just replace the clutch.

It's changing gear fine.  Would you expect that if the plate is broken?  When you say 'zombie clutch'...?

43 minutes ago, jonmad said:

'zombie clutch'

Quick straw poll in my office has the clutch saying "brains, brains..."

 

Oh and do you have red on you?

1 hour ago, jonmad said:

It's changing gear fine.  Would you expect that if the plate is broken?  When you say 'zombie clutch'...?

 

Clutch disengagement depends on the non-driven pressure plate, I'm not suggesting that's damaged.

 

There really aren't many things that could cause engine vibration independent of gear or road speed. The clutch and flywheel or the crankshaft is about all there is and I doubt your crankshaft is out of balance since that would mean a major manufacturing defect, which leaves...

Great, I really appreciate your insight and explanation.  Will investigate a new clutch.

I had a really strong vibration due the car battery top plastic cover/fuse holder not sitting properly in its place. I could feel the vibration on the gas pedal, steering wheel... but only above 2200rpm (diesel)

2 hours ago, sepulchrave said:

 

Clutch disengagement depends on the non-driven pressure plate, I'm not suggesting that's damaged.

 

There really aren't many things that could cause engine vibration independent of gear or road speed. The clutch and flywheel or the crankshaft is about all there is and I doubt your crankshaft is out of balance since that would mean a major manufacturing defect, which leaves...

 

Curious - if it was the friction plate, wouldn't it vibrate when in neutral and stationary?

1 hour ago, jonmad said:

 

Curious - if it was the friction plate, wouldn't it vibrate when in neutral and stationary?

 

I think that's what the rattling you can hear is.

Look, I'm not saying it's definitely the clutch, I'm saying that's where I'd start because it can't be much else, you can't prove a negative until you inspect it and the abuse you give it suggests that it may be damaged.

Gotcha.

Hi.  fwiw it probably won't change your suggested diagnosis (the car is going to a garage next week for MOT and for this to be investigated), but I did a little test drive.

- excessive vibration in all gears whilst accelerating up through about 2000-2800 rpm, then it smoothes out (harder to detect in 1st as I pass through that range quickly)

- excessive vibration in all gears whilst decelerating (easing off or foot off the gas, but in gear) down through the same range

- no significant vibration at constant throttle within that range

- no significant vibration when dipping the clutch in any gear from about 2800-3000rpm and the revs fall quickly to idle

 

Cheers,

Jon