Rotten egg/burning smell from Audi A3 (2000)

[yosamuel]

Hi all,

When I pull out of my garage I make a left turn and normally have to wait for the lights to change at the top of a steep hill. Today was no different.

Once I had climbed the hill, passed the lights and was continuing along the main road I noticed a strong rotten egg smell, followed by the smell of burning. Arriving at a set of lights I killed the engine and the smell passed.

Cautiously I returned home (after getting stuck in a one-way system—this involved a good five minutes of stop-start driving), by which point the smell had gone. I visually inspected the exhaust system and engine bay but saw nothing suspicious, so set out on my 8 mile journey again. The smell failed to reappear.

Busted cat or something else?

Thanks.

[eybic]

I know in the mid nineties, it was quite normal to get that smell and it was from the Cat's, not sure if thats the case with a 2000 car but personally I wouldn't worry.

[andyiley]

It does still happen with some cats & is nothing to worry about, it is just the honeycomb getting up to temperature, and is quite normal for the first couple of minutes.

Less obvious with the metalic honeycomb type cats rather than the (normally cheaper) ceramic type cats (if I remember correctly) or could be the other way round.

[yosamuel]

Thanks guys—I’ll see how it goes. I’m hoping it was just a combination of the cool weather, and added strain from the incline.

It was more the burning smell that worried me.

MOT on Thursday, so I’ll find out for sure then.

[Nick1point9]

I take it it's a 1.9 tdi? My mum had a 98 golf with that engine and had intermittantly had the same symptoms, but VW never got to the bottom of why.

[honestbob]

I'd have an outside bet on clutch slip.
Steep hill,holding on clutch perhaps?,pulling away from traffic lights.
Stop start traffic etc. Consider it.

[Avidfanofstuff]

DPF regen?

[yosamuel]

This is the 1.8 petrol engine (sorry, I should have stated that earlier).

honestbob said:

I'd have an outside bet on clutch slip.
Steep hill,holding on clutch perhaps?,pulling away from traffic lights.
Stop start traffic etc. Consider it.

I took it for a 100 mile round trip (city, motorways, B roads) and the smell didn’t return. I hadn’t considered it could be related to the clutch but I noticed yesterday that I was having trouble pulling away (almost like a hiccup as I released the clutch) which I put down to my own technique rather than a technical fault (I have never experienced a failing clutch before).

Thanks for suggesting this, I’ll raise it when I go for the MOT.

[Vince70]

A good way to test if its the clutch is try pulling away with the handbrake on.

If it stalls its ok if not then it's on its last legs, but saying that if your gentle using the clutch it may last ages before you need a new one.

The first signs are normally clutch slip when putting your foot down in high gears.