Volkswagen Lupo - Rattling from engine at idle

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Tue 7 Mar 2017 19:22
Volkswagen Lupo - Rattling from engine at idle - gavmoffat
Hi all

Bought a very low mileage Lupo as a runaround the other week and starting to worry as some problems have emerged! Any ideas much appreciated!

1. Noticed today a fast, rattling sound coming from the engine at idle. If I depress the clutch it goes away and it smooths out quickly if I rev the engine.

2. Slightly dirty smell comes through the vents at times, also mainly at idle. I've not got the best sense of smell so can't work out if it's a burning or exhaust smell.

3. Brake lights have failed twice, giving an EPC warning. Replaced brake light switch at an independent garage but failed again a few days later. Not sure if garage did a bodge job or it's something more.

Think I might have a lemon here but live and learn!
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Tue 7 Mar 2017 21:42
Volkswagen Lupo - Rattling from engine at idle - elekie&a/c doctor

1 ,could be clutch or gearbox problem,if it drives ok ,then more likely the former.

2, smell possibly a broken or perished engine breather pipe allowing oil fumes to enter cabin.

3,Brake light switches are a favourite failure on all VAG models. Was this a genuine switch and has it been fitted corectly?

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Tue 7 Mar 2017 22:17
Volkswagen Lupo - Rattling from engine at idle - gavmoffat
Thanks!

1. On second thoughts I might be being a bit paranoid about this one. It's more of a ticking and is entirely in sync with the engine running. Car does seem to drive perfectly and at 30k miles would hopefully not need a new clutch. Best I get a second opinion on the noise from a mate who is a bit more car-savvy before I give to a mechanic who might just say it needs a costly fix.

2. Will look this one up asap, cheers.

3. Possibly not fitted properly. Handed it into an independent mechanic, it worked for a few days now is working only when brake fully depressed. One other issue is that the EPC light doesn't come on all the time during the fault, only sometimes. Either I take it back to he same guy or get a £50 fix at VW.

Edited by gavmoffat on 07/03/2017 at 22:20

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Tue 7 Mar 2017 22:45
Volkswagen Lupo - Rattling from engine at idle - Big John

What is the age of car, engine size , engine code?

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Tue 7 Mar 2017 23:22
Volkswagen Lupo - Rattling from engine at idle - gavmoffat
2002 Lupo 1.0. Engine code should be AUC.
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Wed 8 Mar 2017 09:06
Volkswagen Lupo - Rattling from engine at idle - gavmoffat
Quick update. The rattly noise comes from the passenger side and could be better described as a vibration. It's only really perceptible from outside with the bonnet up.
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Wed 8 Mar 2017 10:17
Volkswagen Lupo - Rattling from engine at idle - Avant

If it's really done only 30,000 miles in 15 years, in many ways it'll have had a harder life than if it had done 130,000. I hope you didn't pay over the odds because of the low mileage.

You have to expect some imperfections: just keep it running and with luck it'll keep going for long enough to justify its cost before it becomes uneconomic to repair and has to go for scrap.

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Wed 8 Mar 2017 10:30
Volkswagen Lupo - Rattling from engine at idle - SLO76
Likely to be the hydraulic tappets. There are a number of things that can contribute to the downfall of the tappets. These are infrequent oil changes, use of a non V.A.G./M.A.N./Knect oil filter without a non return valve, and a blocked oil pick up pipe in the sump.

The small oil ways in the tappets are prone to clogging up with oil debris, which can come about by using poor oil or skimping on the oil changes. Remember that most V.A.G. engines need an oil change at least every 10,000 to 12,000 miles or 12mths whichever comes soonest. If you do a lot of small journeys, where the oil does not reach operating temperature then the oil must be changed more frequently.

This is often the weakness of low mileage cars like this. I'll hazard a bet the oil has typically been in it for several years at a time?
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Wed 8 Mar 2017 13:30
Volkswagen Lupo - Rattling from engine at idle - gavmoffat
Thinking it might be a noisy / worn clutch bearing. It's coming from the gearbox area, the sound fits with a few videos I looked up and it goes away as soon as I depress the clutch.
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