Technical Tapping (?) sound coming from under the hood

[GrandeFizzy]

Hi guys

I have a 2006 Grande Punto with a 1.2l 8V petrol engine. The noise I'm referring to has been present for as long as I have owned the car (about 5-6 months now). So far I've only had to replace the spark plugs and ignition coils. This car has 232k kilometers and has only ever had one owner previously. The car has been serviced regularly with a service booklet to back it up.

The sound is constant, it doesn't change depending on the engine temperature, its audible from the outside and it follows the speed of the engine of course. I have attached two videos with the noise, which appears to be coming from the top of the engine.

I just want to add that this is my first car, therefore I might not be knowledgeable on some stuff!

 

[GrandePunto PL]

If this is your first car ever, go to YouTube and watch 20-30 different videos about Fiats, listen to engine sounds (1,2 and 1,4 8V).
Clicking is normal, but a little bit too loud (maybe it's the camera/phone, recording makes everything worse).
Maybe you need a valve clearance check: https://www.fiatforum.com/guides/valve-clearance-check-and-adjustment-1-4-8v.824/
But on top of that, you have a constant noise, hum, like an alternator/AirConditioning belt tensioner is worn. Empty A/C can make a noises too.

If you record such things, do also a rev-up, increase the speed (1000->2000->3000 RPM) of the engine, so we can hear the changes. Not just idle rpm.

The car has been serviced regularly with a service booklet to back it up.

Really? Wanna bet, that some things were neglected, they've skipped some maintenance items (like a mentioned "valve lash")?
There is a lot to check if you are past 200000 km mark... Things beyond the official schedule in the Owner's Manual (Handbook).

 

[GrandeFizzy]

If this is your first car ever, go to YouTube and watch 20-30 different videos about Fiats, listen to engine sounds (1,2 and 1,4 8V).
Clicking is normal, but a little bit too loud (maybe it's the camera/phone, recording makes everything worse).
Maybe you need a valve clearance check: https://www.fiatforum.com/guides/valve-clearance-check-and-adjustment-1-4-8v.824/
But on top of that, you have a constant noise, hum, like an alternator/AirConditioning belt tensioner is worn. Empty A/C can make a noises too.
View attachment 465318
If you record such things, do also a rev-up, increase the speed (1000->2000->3000 RPM) of the engine, so we can hear the changes. Not just idle rpm.

Thank you for your reply!

I have watched a couple videos on youtube about this, which is why I never asked about it until now because I thought it was normal, although like you said mine does sound a bit too noisy. I think I managed to only find one video with that engine that makes the same noise as mine, or at least a similar noise.

Also about the A/C, I will say that I had it refilled last month. One of my friends also suggested that the A/C tensioner might be worn out.

I went out and filmed a video of it revving

 

[GrandeFizzy]

Really? Wanna bet, that some things were neglected, they've skipped some maintenance items (like a mentioned "valve lash")?
There is a lot to check if you are past 200000 km mark... Things beyond the official schedule in the Owner's Manual (Handbook).

Could definitely be a possibility, I should've clarified that by "regular service" it meant oil changes, air filter changes etc.

Last belt service was done at 189km, in 2018 or 2019, I can't remember exactly.

 

[AnthonyH]

Thank you for your reply!

I have watched a couple videos on youtube about this, which is why I never asked about it until now because I thought it was normal, although like you said mine does sound a bit too noisy. I think I managed to only find one video with that engine that makes the same noise as mine, or at least a similar noise.

Also about the A/C, I will say that I had it refilled last month. One of my friends also suggested that the A/C tensioner might be worn out.

I went out and filmed a video of it revving

It sounds normal when its idling, but its growling when you rev it.

I think it needs repairs of some description, but i couldn't guess what those repairs would be.

 

[GrandePunto PL]

Not so bad (rev-up). Some Fire family engines sound worse and still drive fine (acceptable).
Just do some maintenance (things never done by the previous owner), that's it for now.
If it drives OK (has power), no leaks, will pass emissions test = OK, don't "repair" it.

 

[varesecrazy]

Could definitely be a possibility, I should've clarified that by "regular service" it meant oil changes, air filter changes etc.

Last belt service was done at 189km, in 2018 or 2019, I can't remember exactly.

Worth getting the "rubber" belts changed,

My 500 is 2018 (same FIRE motor) and belts are due Now due to age

 

[GrandeFizzy]

If it drives OK (has power), no leaks, will pass emissions test = OK, don't "repair" it.

Everything seems fine, the car drives okay, nothing is leaking (oil levels are fine, coolant levels are fine too)

Worth getting the "rubber" belts changed

Thats coming up pretty soon regardless!

Anyway, I have some news I guess. Next week, I'm taking the car to my mechanic to see exactly what the noise is. Might feel like an eternity, but it is what it is. I'll post updates when there's something noteworthy to write about.

I would still like to hear other people's thoughts on this, so please do continue writing.

Thank you!

 

[Pugglt Auld Jock]

Everything seems fine, the car drives okay, nothing is leaking (oil levels are fine, coolant levels are fine too)

Thats coming up pretty soon regardless!

Anyway, I have some news I guess. Next week, I'm taking the car to my mechanic to see exactly what the noise is. Might feel like an eternity, but it is what it is. I'll post updates when there's something noteworthy to write about.

I would still like to hear other people's thoughts on this, so please do continue writing.

Thank you!

The first thing to say is that it doesn't sound like anything needs emergency attention but, there are noises there which would annoy me and shouldn't be ignored long term. The tapping sound might well be wide tappet clearances. This is very easy to check if you have some mechanical experience as all that's needed is to remove the cam cover and use a set of feeler gauges to check the clearances as you rotate the engine to set each cam lobe up to maximum clearance. Trouble is that if you find wide clearances sorting it is much harder involving establishing shims of the correct clearance and then swopping them out for those in place. One of the biggest problems with doing it is actually finding someone who has/or a supplier of, the many different thickness of shims. The other noise which is very evident is louder when you hover over the belt end of the engine so I'd suspect alternator/air com pump, aux belt tensioner, maybe cam belt tensioner, etc. Checking this out would be an ideal job for a "listening stick" and/or "listening tube".

A small amount of tappet "rattle" (due to wear in the followers or excess clearance/gap) is not unusual in these engines as they age, our Panda has a small amount and always sounds loudest at start up before the oil circulates. When you hear just one or two getting a lot louder than the others it's probably an indication that you will need to take the cover off and investigate. They tend to run on "for ever" even with quite a noisy tapping going on. I'm expecting something else to condemn ours before I might have to do something about them. A worn bearing in a belt tensioner/alternator, air com pump is probably more worrying and, potentially, cheaper to sort.

The noises are so obvious I will be surprised if your mechanic doesn't sort this out for you.
Good luck and do let us know how it all works out.

 

[GrandeFizzy]

The first thing to say is that it doesn't sound like anything needs emergency attention but, there are noises there which would annoy me and shouldn't be ignored long term. The tapping sound might well be wide tappet clearances. This is very easy to check if you have some mechanical experience as all that's needed is to remove the cam cover and use a set of feeler gauges to check the clearances as you rotate the engine to set each cam lobe up to maximum clearance. Trouble is that if you find wide clearances sorting it is much harder involving establishing shims of the correct clearance and then swopping them out for those in place. One of the biggest problems with doing it is actually finding someone who has/or a supplier of, the many different thickness of shims. The other noise which is very evident is louder when you hover over the belt end of the engine so I'd suspect alternator/air com pump, aux belt tensioner, maybe cam belt tensioner, etc. Checking this out would be an ideal job for a "listening stick" and/or "listening tube".

A small amount of tappet "rattle" (due to wear in the followers or excess clearance/gap) is not unusual in these engines as they age, our Panda has a small amount and always sounds loudest at start up before the oil circulates. When you hear just one or two getting a lot louder than the others it's probably an indication that you will need to take the cover off and investigate. They tend to run on "for ever" even with quite a noisy tapping going on. I'm expecting something else to condemn ours before I might have to do something about them. A worn bearing in a belt tensioner/alternator, air com pump is probably more worrying and, potentially, cheaper to sort.

The noises are so obvious I will be surprised if your mechanic doesn't sort this out for you.
Good luck and do let us know how it all works out.

Thank you for this reply!

I don't have any mechanical experience, so I'd rather not try it myself, but your insight is extremely helpful.

Could you also describe the noise you're hearing from the belt, please? I'm having trouble noticing it myself.

 

[Pugglt Auld Jock]

Thank you for this reply!

I don't have any mechanical experience, so I'd rather not try it myself, but your insight is extremely helpful.

Could you also describe the noise you're hearing from the belt, please? I'm having trouble noticing it myself.

Hi. The belt noise? I actually wouldn't attribute it to the belt - to me it's just not a "Belt noise" but much more likely to be a ball race type bearing in the early stages of failure so "running rough". If I were standing there beside you, having first checked the belt because that's so simple to do, we could try a listening stick - so, something like a long screwdriver or metal rod (or automotive stethoscope if you're wanting to splash the cash) Place the blade end of the screwdriver against the component casing (so just behind the pulley on the alternator or air con pump or against the mounting for the tensioner and locate the plastic handle of the screwdriver in your ear. you'll hear the "rough" noise of a worn bearing immediately - Of course, without experience you won't know what a good or worn bearing sounds like and also, without experience there's a very real chance of the screwdriver slipping and getting "snatched" by the belt or pulley itself which would be VERY dangerous. A listening tube is simply a convenient length of tubing - mine is a piece of nylon tubing which I like because being quite stiff it's easy to control but some fish tank tubing, fuel pipe etc can work well. It needs to be long enough for you to be able to stick one end in your ear while you watch what you're doing with the other end. To use it, with one end stuck in your ear, you move the other end around near to the places you suspect the noise is coming from. Both methods of detection are often used one after the other because one method will allow you to hear some noises which the other won't detect. Both methods run a high risk of personal injury as they have to be done with the engine running and there are lots of moving parts the stick or tube can be snagged in which might cause severe injury. The health and safety man really doesn't like it! However I've been doing it, very carefully, for over 50 years and never hurt myself - so far?!

 

[GrandeFizzy]

Hi. The belt noise? I actually wouldn't attribute it to the belt - to me it's just not a "Belt noise" but much more likely to be a ball race type bearing in the early stages of failure so "running rough". If I were standing there beside you, having first checked the belt because that's so simple to do, we could try a listening stick - so, something like a long screwdriver or metal rod (or automotive stethoscope if you're wanting to splash the cash) Place the blade end of the screwdriver against the component casing (so just behind the pulley on the alternator or air con pump or against the mounting for the tensioner and locate the plastic handle of the screwdriver in your ear. you'll hear the "rough" noise of a worn bearing immediately - Of course, without experience you won't know what a good or worn bearing sounds like and also, without experience there's a very real chance of the screwdriver slipping and getting "snatched" by the belt or pulley itself which would be VERY dangerous. A listening tube is simply a convenient length of tubing - mine is a piece of nylon tubing which I like because being quite stiff it's easy to control but some fish tank tubing, fuel pipe etc can work well. It needs to be long enough for you to be able to stick one end in your ear while you watch what you're doing with the other end. To use it, with one end stuck in your ear, you move the other end around near to the places you suspect the noise is coming from. Both methods of detection are often used one after the other because one method will allow you to hear some noises which the other won't detect. Both methods run a high risk of personal injury as they have to be done with the engine running and there are lots of moving parts the stick or tube can be snagged in which might cause severe injury. The health and safety man really doesn't like it! However I've been doing it, very carefully, for over 50 years and never hurt myself - so far?!

Those health and safety men always try to get in the way, don't they? But you've kept them off your back!

I have considered using a screwdriver to help find what it might be, but as you've said, I probably wouldn't be able to tell anything. I will bring this up to my mechanic, it's definitely worth having a look at and hopefully he'll notice it as well.

Thank you for your time! I wish you all the best