Was driving home today and the engine management light came on. I went to a local mechanic at a back street garage, he plugged it in to the diagnostic and it came up with three codes which he said indicated a split in a vac hose, he checked them and said they were all fine so cleared the light and said to go back if the light came back on.

While he had the bonnet open he heard that there was a bit of a rattling noise from the back of the engine and said that the timing chain needed replacing. The cam belt was changed around 5,000 miles ago. The car is a 2001 model with 59000 miles on the clock and has had 11 services in its life.

He quoted me £400 for the timing belt change and said it would take best part of a full day to do. He said it would be very messy if I didn't get it done and it went.

I then took it to a second garage and the guy there listened to the engine and said he could see why the first guy said that but in his opinion it was normal and there was no problem.

Admittedly I did hear the noise but I'm not clued up enough on engines to know anything about it.

Think I have something to worry about?

hmmm if it made a ratteling noise then it would be broken, if it is broken then your engine is broken.

Belts dont make a ratteling noise and timing chains dont need replacing.

Which model do you have?

I have the Audi A4 2.0 SE petrol automatic from 2001 (newer model from that year).

It has had it's cam belt changed recently and had a service 1000 miles ago. I've got it booked into a third mechanic tomorrow for another opinion. It did make a noise like rattling but it drives well and the only codes on the diagnostic were to do with the vac system which were apparently fine!

To be honest I think so.

I wouldn't take any chances. Rattling from an engine isn't normally a good sign.

Glen!

Its not a fault with the timing chain, it is the chain tensioner, although if you was changing the tensioner it would be a more economical repair to have the chain and chain guide replaced at the same time. This used to be common with the ALT code engine with similar mileage to yours.