I have a noisy 1.8 TS 1999 - very rattly under 2000 revs. No performance problems, leaks or other nasties, just very noisy! The noise comes from the general area of the timing belt cover. (I have read that over time the variable valve timing mechanism can become worn, but I'm not sure what the symptoms are, and I'm fairly sure that loss of power would be one of them - I have no perceivable loss of power). What's a likely diagnosis and fix??
Thanks in advance - Rich
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Just to give you an idea of the noise, it sounds like a diesel on tickover! Rich
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The timing belt tensioner is broken.
Open the cover to confirm.
DO NOT DRIVE THE CAR.
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Some Fiat/Alfa engines have problems with the variator which can cause the engine to sound like a diesel when idling. The variator is an electrical solenoid located at the top of the engine at the timing belt end.
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Thanks - I'm pretty sure that it's not the timing belt tensioner, although I'll take a good look. The engine has been making the same noise for a year or so and the tensioner was changed a couple of years ago along with the bearings and the belt. If it really is the tensioner I shall be taking the car directly to the "professionals" that replaced it at the main dealer. Frankly I'm not impressed with French Fiat/Alfa/Lancia technicians. Having had a Lancia Delta Integrale Dealer Edition (15 made) almost destroyed by one who was "tinkering" instead of changing the flexipipe on the exhaust, they are quite understandably not on my list of recommended garages...(no offence to any F/A/L technicians - just my experience!)
The variator - sounds interesting - is it a part which is easy for a competent amateur to a) recognise and b) test and change if necessary?
To be perfectly honest with you, I would be happy to live with the noise but I'm about to try to sell the car, and I wouldn't buy it if it sounded like that (if you know what I mean!)
Thanks in advance
Rich
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Hi I would have a really close look at the timing belt tensioner.
I had a 156 and it was making a rough noise at low revs (noise would follow the reves of the engine). Drove it to Alfa dealer and they told me not to drive it anymore as tensioner was about to break.
Fixed under warrantee (Car under 3 years old)
Hope it is something different.
Cheers
Jlo
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Back when the twinspark engines first came out, Alfa soon realized that a lot, but not all were prone to one particular problem. The 2-litre does not suffer from it, but the 1.6 and I think the 1.8 does too.
The cam variator is prone to wear. It is designed to increase the oil supply to the top of the engine at above 3000rpm as it is a high revving engine. It also changes the timing of the ignition (advance, I think). Get this wrong or with a worn part, and the engine clatters.
My 1.6 TS sounded like a diesel at 36k miles - variator changed under warranty and then sounded lovely again. I have had the offending item changed at 72k and 108k along with the cambelt and tensioner and so the car hasn't had the chance to sound like a diesel. I seem to remember that the design of the variator was changed to overcome this problem.
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Variator sits at top of engine and varies the camshaft timing as a function of RPM. Failed variators make the Diesel noise you describe.
Pre-2000 variators were junk and failed regularly. Get the later improved version and it should last a bit longer. They are under £100 IIRC. Keeping the oil fresh helps them last longer.
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Perfect! I'm off to the parts shop....PS - could I change the part easily myself???
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