F355 noisy on cold tickover

[Andyandyhall]

Hi my 1999 F355 makes a heavy 'clanking' sound on tickover when started from completely cold, it lasts for about 3 minutes and is then gone. Once warm it's absolutely fine and sounds great. The car is lowish mileage 20,000, gets service annually and gets used fortnightly for a decent run and is otherwise in great shape.

I was wondering if anyone else has noticed this with theirs and if it's anything that needs further investigation?

[Chrism355]

Probably exhaust by pass as these rattle as they get older, either put up with it or fit the Capristo unit

[HardtopManual]

Could be one of a number of things, but most likely a bit of piston slap until they expand as they warm up.

[EVOeng]

Is it coming from the RHS rear?

[Cerberaherts]

In order of most common;

1. Exhaust bypass valve

2. Broken isolator bush in rear silencer mounting

3. Oil pump chain tensioner pad broken up.

All more prevalent when engine cold. It needs checking!

[Andyandyhall]

Thanks guys, hard to isolate the area it's coming from, i'll get it looked at after the holiday.
hopefully i've caught it before it creates a bigger more expensive issue....

[F355GTS]

Could be the Air pump - lower rear right of engine bay. They're prone to failure

[Andyandyhall]

Gotta love the internet, there's a mine of info on this issue...

http://www.ferrarichat.com/forum/348-355-sponsored...

http://www.ferrarichat.com/forum/348-355-sponsored...

[gav dunn]

Possibly a cam follower, (hydraulic tappet) noisey until fully pumped up with oil! Hard to diagnose without hearing the noise.

[Andyandyhall]

gav dunn said:

Possibly a cam follower, (hydraulic tappet) noisey until fully pumped up with oil! Hard to diagnose without hearing the noise.

Many thanks, the more ideas to explore the better so I can best try and isolated the problem.

[tony h]

i'd listen to Cerberaherts; he mends these things for a living :-)

[Andyandyhall]

Cerberaherts said:

In order of most common;

1. Exhaust bypass valve

2. Broken isolator bush in rear silencer mounting

3. Oil pump chain tensioner pad broken up.

All more prevalent when engine cold. It needs checking!

Well done that man, the F355 has been in and this was the problem


It was the oil pump chain
tensioner creating the noise. The nylon pad that the oil pump chain runs on
had come adrift from the tensioner mechanism. The new tensioner from Ferrari
has been made with a much better design that increases the tensioner
pre-load on the chain and also prevents the nylon pad from coming adrift by
locking it in place with metal tabs.

[Cerberaherts]

Yes they are buggers for doing that! The revised design (carried over to the 360) can also suffer with it too despite the modifications...