Technical Loud tapping when starting up

[Chiddleston]

My Fiat Panda MyLife 1.2 has developed another problem, but two in 6 years isnt bad, hopefully. Starting it up, whether the engine is cold or hot there is a loud metalic tapping noise. From the cabin it sounds like a 70's VW Beetle, but with bonnet open its like someone tapping the engine top with a hammer. Press accelerator the tapping gets louder, but leave it idling for a few minutes the tapping isnt too loud, theres also the occasional drop in revs for about a few seconds but not enough to stall. It usually stops after a minute or so and the car will run perfectly well until turning off and restarting.

Anyone know if its this likely to be needing valve adjustent? or tappets? neither have been done before, mechanics never bothered doing them when in for a service. Car had oil change and service end of last november, has just passed 100,000 miles and due a new cambelt at around 105000 as the previous owner had original changed at 35k.

Thanks

 

[timmycm850]

Morning.

Sounds like a worn camshaft lobe to me,
If your planning to do the cambelt soon then if you take the cam cover off in advance you will see if you need to be addressing the camshaft at the same time.
Tim

 

[DaveMcT]

Does the 1.2 have oil filled cam followers? The ones on my (yes, I know it's different) 1.3 diesel were badly worn on the ball-ends. Some were falling apart before the chain broke. I found needle rollers in the sump.

 

[timmycm850]

Probably best we confirm the year of the car, is it 1.2vvc post 2012?.

Tim

 

[DaveMcT]

Cam variator and/or its oil solenoid valve?

 

[Chiddleston]

Cars a 2011, 61 reg. 1.2 engine. Fluids are all OK, no water or oil leaks or excessive usage, Spark plugs were new in november, have pulled those again and all OK. Its done 5000 mile since last oil change. Not sure about it being the camshaft, as theres no misfire at any speed but then, im no expert.

 

[koalar]

Have a compression test done, might save a lot of wasted time

Or post a video as noises are difficult to describe

Sounds like it's gone between cylinder 1 and 2

Normally sounds worse under heavy acceleration and clears up when warm, metallic, sharp, tapping

Revs drop and pick up at idle

Moisture on top of the throttle body

There quite a few reasons for a knocking noise at start up. You can work through all the possibilities. Which is time consuming. Or confirm or eliminate one of the most likely first

 

[Yolanda]

My Fiat Panda MyLife 1.2 has developed another problem, but two in 6 years isnt bad, hopefully. Starting it up, whether the engine is cold or hot there is a loud metalic tapping noise. From the cabin it sounds like a 70's VW Beetle, but with bonnet open its like someone tapping the engine top with a hammer. Press accelerator the tapping gets louder, but leave it idling for a few minutes the tapping isnt too loud, theres also the occasional drop in revs for about a few seconds but not enough to stall. It usually stops after a minute or so and the car will run perfectly well until turning off and restarting.

Anyone know if its this likely to be needing valve adjustent? or tappets? neither have been done before, mechanics never bothered doing them when in for a service. Car had oil change and service end of last november, has just passed 100,000 miles and due a new cambelt at around 105000 as the previous owner had original changed at 35k.

Thanks

Has the cam belt degraded to the extent that it's slipped a couple of teeth and the pistons are just nipping at the valves creating the noise but not enough do any damage.

 

[The Panda Nut]

Yolander makes a scarey suggestion. I would check this fast. Valve clearances are not traditionally adjustable. Set by shims and I was told here its .unusual for these to require redoing. I had one of ours done at about 50K and they were still perfect. If oil is bad you will certainly hear this on start up. I used Petronas Syntium and it was awful. So bad I think it was not genuine. Changing the oil for Castrol edge stopped all the rattling stone dead. I agree visual inspection of the camshaft is also a good idea, You can set it TDC and see if the cam is correctly aligned. This will assist with a belt check. Check the cam and the clearances while the cover is off. Could be a small end but that would be noticable whatever.

 

[koalar]

Unlikely to be timing belt

As its fine after it's warmed up

Lots of things it could be, sticking valves and so on

But here what a a blown head gasket can sound like

Normally goes away when the engine as run for a bit

As its fairly common I would eliminate it

Then move to other possibilities

Here's mine


And an example of the noise

 

[koalar]

Stupid me

Here mine and forgot to post the link

Running bad, cylinder head | FIAT Panda (Mk3)

Right let's start with the driving symptoms Knocking noise when accelerating cold engine, clear up when hot poor power at lower revs, bogs down then picks up, clears up when hot stalls at junctions erratic idle, revs rising and falling, sometimes a bit shaky at idle judder on pulling off...

www.fiatforum.com

Mine was Identical to the noise in the video

Video would help a lot especily if you move the camera around

We would be able to tell if the sound is from the top left right front or back as the microphone is very sensations to distance, more so than your ears


Also does the sound alter with gear or change if you press the clutch


The drop in revs points to an engine problem. But if a coincidence (unlikely) it could be just about be anything connected to the engine and spinning