Technical Erratic tapping sound.

[SIMONrun]

Hi all.
My 2009 Panda 1.1 has a curious "tapping" sound from the engine.
Sometimes it does it- sometimes not- always on tick-over or low rpm.
Sounds perfect at all other times. Oil and filter was changed last week.
Only done 53k and runs perfectly otherwise.
Thoughts ?
Cheers.

 

[koalar]

impossible from the information given.

loose airbox is fairly common ?

try taking a video on a phone move it around. the microphone is sensitive to distance. Should be able to work out if its top, bottom, left or right

 

[DaveMcT]

Does the noise change with the clutch pedal up or down?

 

[SIMONrun]

Does the noise change with the clutch pedal up or down?

Hi- No it doesn't...

impossible from the information given.

loose airbox is fairly common ?

try taking a video on a phone move it around. the microphone is sensitive to distance. Should be able to work out if its top, bottom, left or right

Location seems to be mid-lower head- to the rear... though with metallic type sounds hard to say...

 

[koalar]

take the air cleaner off

better or worse ?

the injectors do tick slightly ! it not this your listening to

is it worse from a cold start

 

[DaveMcT]

I asked about the clutch pedal because a noisy gearbox input bearing will rattle when clutch pedal is not in use but go away when clutch is pressed down. That's not happening so good news.

I think you will have to jack up the car and get underneath to check for things like broken exhaust clamps or anything else that's loose. Also look for cracks in the alternator case. The laminated core can corrode leading to strange noises as the rotor starts to bind.

Please note this is guesswork. You will have to look and listen for the noise with engine running.

 

[SIMONrun]

Thanks for the replies- but no- it's not a "loose" or "rattle" noise.
It's totally rhythmic to the rpm- 1 cylinder it seems to me- just like an old school camshaft tap, but clears after 1500 rpm...
The oddity is it's erratic. Today all is quiet !! Not a squeak from cold start up !
I guess I'll ignore if for now- and wait for it to develop !