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Discussion Starter #1
Hello all

My 156 GTA has a rattle from the engine area when it's cold and under load.
It sounds like an exhaust rattle and after extensive investigation my alfa mechanic concluded that it was coming from the Cat in the rear exhaust manifold. We have just replaced both exhaust manifolds (2nd hand parts which have done 40k) and the sound is still there!

Does anyone have any idea what this could be?

I'm beginning to wonder if it could be an engine noise as opposed to an exhaust noise as it occurs under similar conditions as a pinging problem I had in my 147.
Would a GTA engine only ping when cold???

Any advice would be very much appreciated.
(Full Cam Belt change done 18 months / 20k ago. Current mileage is 103k)

Cheers
 

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Discussion Starter #3
I couldn't say categorically that I it does't occur above 2k RPM but YES I think that is the general case.

Is there any way of testing whether or not it is the big end bearings?
 

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Any chance of a video of the sound on Youtube?
 

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Discussion Starter #5
I can try to get a video up if I can.

The trouble is that the noise only occurs under load / when driving and even then it is not the most predominant of noises. It sounds like a heat shield or Cat rattle.
 

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Why didn't u replace with catless gtv manifolds? Would have been I nice upgrade if u went to trouble of replacing with standard manifolds.
 

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Does the rattle increase and decrease in time with engine revs, like something rotational within the engine?
 

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Has she run low on oil for an extended period of time? Ever had an oil pressure warning light? Does sound like big ends- best to catch that sooner rather than later and have the bearing shells replaced. Leave it too late and it could be a disastrous affair...
 

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Discussion Starter #9
Here is a link to a youtube clip of the sound (stationary).
Rattle when cold on Alfa 156 GTA - YouTube

Pud you will be able to hear for yourself but the noise does seem to speed up with the engine revs.

I've never had any oil issues with it, I change the oil every 6 months and use Silkolene Pro S 10w 50.
 

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Jono,

There have been several videos posted on YouTube in the past and it has been fixed by having the cambelt retensioned, or going for a full replacement, as I did, with all new parts. I posted one myself but deleted it later - very similar sound to yours.

In my case, the belt was about 2 years old, but getting it done cured the noise. I was told it's the tensioners that gets worn and causes the tapping. In my case, the sound was louder near the cambelt cover.
 

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Discussion Starter #11
Jono,

There have been several videos posted on YouTube in the past and it has been fixed by having the cambelt retensioned, or going for a full replacement, as I did, with all new parts. I posted one myself but deleted it later - very similar sound to yours.

In my case, the belt was about 2 years old, but getting it done cured the noise. I was told it's the tensioners that gets worn and causes the tapping. In my case, the sound was louder near the cambelt cover.
Thanks for your reply, I will explore to see if mine comes from the cam belt area.
When your's made this noice did it occur only when the engine was cold?
 

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I'm not going to be able to view that video until I get home on the 28th.
 

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I had a similar issue and it was the cambelt. It had only been done two years previously by a main dealer. The garage thought it must have been incorrectly tensioned.
 

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Discussion Starter #15
So I've just fired up the engine again from cold and popped the bonnet.

The noise is definately coming from the cam belt area although I would say it seems to be loudest at about one hand's width to the right of the cam belt cover.

I guess the good news is that the noise certainly does not sound like it is coming from deep within the engine.

Do you thing that, given the above, it is a strong possibility that the cam belt / tensioner is the source?
 
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So I've just fired up the engine again from cold and popped the bonnet.

The noise is definately coming from the cam belt area although I would say it seems to be loudest at about one hand's width to the right of the cam belt cover.

I guess the good news is that the noise certainly does not sound like it is coming from deep within the engine.

Do you thing that, given the above, it is a strong possibility that the cam belt / tensioner is the source?
I've heard a very similar sound on a 1.6 TS......a new tensioner sorted the problem.
 

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I should have been more specific, it was the tensioner. It seems odd how many people it's happened too. Maybe the dealer tensioned it properly and there were a dodgy lot of tensioners.
 

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Hey!
Before changing the tensioner check the rear cat-valanx below the car, mine have had a similar noise when cold as the inner life of both cat-containers where loose.
kind regards
Dave
 

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Discussion Starter #19
Hello all

Thanks for the good advice.

Assuming it is the cam belt tensioner that is making the noise can you tell me if it is likely to cause any damage if not sorted straight away?

Also, do you know if fixing it is as much work as replacing the whole cam belt kit or is there a shortcut to replacing just the tensioner? I'm just trying to get an idea of cost etc.

Cheers
 

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If that tensioner fails then it will become very very expensive.

Definitely get it looked at right away. If it was my car I wouldn't even drive it.

Cost for a cambelt? Probably about £500 worst case scenario. (everything doing)
 
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