Today I come with an issue and hopefully someone can guide me in the right direction. 

 

A few months ago I noticed a new sound when driving the Fabia. It sounds like a metallic rattle which only happens when in gear and accelerating. It usually happens below 3k RPM and then stops at higher RPM. I've also noticed a long time ago that up hill the car tends to shake as if it doesn't enough power, not sure if that is related at all or not but certainly feels weird.

I have a lot of mechanical sympathy and the rattle when accelerating just sounds wrong. 

 

I've tried recording the sound but it is impossible to hear over the exhaust and intake sound.

 

Any ideas?

 

Thank you everyone

3 hours ago, Fab1493 said:

Today I come with an issue and hopefully someone can guide me in the right direction. 

 

A few months ago I noticed a new sound when driving the Fabia. It sounds like a metallic rattle which only happens when in gear and accelerating. It usually happens below 3k RPM and then stops at higher RPM. I've also noticed a long time ago that up hill the car tends to shake as if it doesn't enough power, not sure if that is related at all or not but certainly feels weird.

I have a lot of mechanical sympathy and the rattle when accelerating just sounds wrong. 

 

I've tried recording the sound but it is impossible to hear over the exhaust and intake sound.

 

Any ideas?

 

Thank you everyone

 

What kind of RPMs are you pulling up hills with? Below 1400 rpm there's practically no torque (no boost). If you're hovering around the 1400 mark the turbo may be coming in/out so it can sometimes feel a tad surgy.

I generally keep in whatever gear that gives me about 2000 rpm so i have full torque available and a bit of headroom in case of someone else struggling in front of me before having to downshift.

 

What mileage do you have on your existing clutch? There's the dampening springs in the clutch plate which do a similar job to a dual mass flywheel (though the flywheel, single or dual mass, does the majority of the dampening), if those dampening springs are going, they can cause rattlilng under light acceleration at lower rpms.

Other than that maybe a heat shield or something, otherwise i don't know of much else.

10 minutes ago, FabiaGonzales said:

 

What kind of RPMs are you pulling up hills with? Below 1400 rpm there's practically no torque (no boost). If you're hovering around the 1400 mark the turbo may be coming in/out so it can sometimes feel a tad surgy.

I generally keep in whatever gear that gives me about 2000 rpm so i have full torque available and a bit of headroom in case of someone else struggling in front of me before having to downshift.

 

What mileage do you have on your existing clutch? There's the dampening springs in the clutch plate which do a similar job to a dual mass flywheel (though the flywheel, single or dual mass, does the majority of the dampening), if those dampening springs are going, they can cause rattlilng under light acceleration at lower rpms.

Other than that maybe a heat shield or something, otherwise i don't know of much else.

Thats probably what I'm doing wrong - I tend to keep my revs well below 2000 rpm. I'm usually about 1200 to 1400 rpm EVEN GOING UPHILL! I'll adjust my driving style as per your comments and monitor from there... 

I've had the car since 9k miles and 18 months old - I've never had a clutch replacement so as far as I'm aware it is the original clutch now with 38k miles. I've had a heat shield loose in another car and this sounds very different to that, but it could be that! I have had my mechanic look at it and he couldn't find anything... but I thought perhaps would be a good idea to see what people think here, I'd rather catch a rattle early on and resolve the issue than let it rattle away and potentially cause more damage.

1 hour ago, Fab1493 said:

Thats probably what I'm doing wrong - I tend to keep my revs well below 2000 rpm. I'm usually about 1200 to 1400 rpm EVEN GOING UPHILL! I'll adjust my driving style as per your comments and monitor from there... 

I've had the car since 9k miles and 18 months old - I've never had a clutch replacement so as far as I'm aware it is the original clutch now with 38k miles. I've had a heat shield loose in another car and this sounds very different to that, but it could be that! I have had my mechanic look at it and he couldn't find anything... but I thought perhaps would be a good idea to see what people think here, I'd rather catch a rattle early on and resolve the issue than let it rattle away and potentially cause more damage.

I'd imagine the clutch is fine then, is it an intermittent sounding rattle or is it reproducible and changes rhythm along with engine rpm?

It does not change rhythm with the engine rpm and it is reproducible. In any gear if I floor the accelerator below 3k rpm it will rattle for a few seconds. It only happens when moving, not when stationary.

Is it a metallic rattle?. What fuel do you use just thinking it may be pinking/detonation. 

10 hours ago, Andymod said:

Is it a metallic rattle?. What fuel do you use just thinking it may be pinking/detonation. 

It is a metallic rattle & I did also think it could be that! I've always ran and still do on Sainsburys regular. The car was also tuned on that fuel over at JBS

Might be worth filling the tank with super unleaded and see if it stops the noise. 

5 minutes ago, Andymod said:

Might be worth filling the tank with super unleaded and see if it stops the noise. 

I just filled it with regular yesterday 😬

It's also just had a full service INCLUDING new spark plugs which I was hoping would stop the noise. Would it be worth adding some sort of fuel additive?

Volkswagen group don't advise any additives although they do actually have genuine additives. Might be worth trying an additive or wait till you need to refuel and try super unleaded.

24 minutes ago, Andymod said:

Volkswagen group don't advise any additives although they do actually have genuine additives. Might be worth trying an additive or wait till you need to refuel and try super unleaded.

I'll wait until needing refuel then and then fill up with some better fuel and see what that does 👍

Im starting to think it could be the way Im driving the car!!! I have a big tendency for getting to as high gear as possible as soon as possible for better fuel economy... and the rattle/clicking noise only happens when using full throttle at low RPM in high gear! Could this be a case of Low Speed Pre Ignition?? 

Never heard of this until this morning but apparently its a thing more common in downsized turbocharged engines... 

The clicking/rattling doesnt happen at all if I modulate the throttle so Im thinking perhaps Im requesting too much of the engine. 

Really you should be driving the car the same as the DSG shifts since this is programmed to both achieve maximum fuel economy but also with mechanical sympathy in mind.

 

So on the flat and with low load/very gradual acceleration it's perfectly fine it get into as higher gear as possible.

 

But as soon as you're going up hill and/or wanting to accelerate past tickling the throttle then you should be shifting down a gear or two.

32 minutes ago, Phil-E said:

Really you should be driving the car the same as the DSG shifts since this is programmed to both achieve maximum fuel economy but also with mechanical sympathy in mind.

 

So on the flat and with low load/very gradual acceleration it's perfectly fine it get into as higher gear as possible.

 

But as soon as you're going up hill and/or wanting to accelerate past tickling the throttle then you should be shifting down a gear or two.

Yep - this is true, Im getting more and more used to it.. I never really floored the accelerator until recently so Im needing to get adjusted to it even though Ive owned for best part of 3 years 

So Ive tried running on super unleaded and the rattle is still there. Im puzzled as to what it could be at this point

Just remove the plastic hose that goes from front grill to the airbox, where the air filter is located and go for a drive. Tell us if the noise was still there or not.

I have a strange suspicion that this will cure the issue...

3 hours ago, krigl said:

Just remove the plastic hose that goes from front grill to the airbox, where the air filter is located and go for a drive. Tell us if the noise was still there or not.

I have a strange suspicion that this will cure the issue...

I can't do that, my car doesn't even have that anymore - It's got a forge intake

Get a tune instead of the intake, more bang for the buck and a K&N insert in original enclosure. Airflow is only restricted by paper filter insert (original).

You go from 90->130ish bhp for a little more money and by my opinion worth it

.

5 minutes ago, krigl said:

Get a tune instead of the intake, more bang for the buck and a K&N insert in original enclosure. Airflow is only restricted by paper filter insert (original).

You go from 90->130ish bhp for a little more money and by my opinion worth it

.

My car is already tuned - it has a custom map from JBS and is running 143 bhp on the dyno. 

This has been resolved! 

JBS has confirmed another owner has complained about the same thing and it turns out it is the wastegate I think they said it was. Apparently it is quite common for them to get "tired" over time and start rattling a bit

Try putting some copper grease on the hinge. It dampens the rattle and doesnt melt away that fast. 

Edited 10 September, 20205 yr by krigl

3 minutes ago, Fab1493 said:

@R44YVY I am also thinking of getting the turbo from the 1.4 put in. Have you had yours mapped yet?

Correct me if Im wrong, but I believe youre running decat right? Whats noise level like? 

Nope not had it mapped as I’ve broke my foot so not been driving or at work etc.

 

the difference is instantly noticeable when putting the turbo in so can’t wait to get it mapped in.

 

Also my gearbox has gone so still I’m trying to find a up rated one that’s compatible. 
 

Yes I’ve got a full custom turbo back exhaust and it’s really loud especially paired with pop and bang map.

Thats excellent, cant wait to have mine done!

 

Not sure if it is viable or not, but have you thought about the 6 speed in the 1.2 110 or the 1.4 140/150? Again, not done any research but just thinking of best way to sort it without over complicating it... 

 

I have the pop map too!! I love the pops but hate how loud the exhaust is when accelerating and its only a catback! Ill probably get some silencers in when going decat...