'Emission Control System' Light

Brill

Member
Hi all,

This is my first post, but have been reading posts for awhile.

Thank you for the copious advice!

I got my car several months ago. Around 10 days ago, the yellow 'Emission Control System' light came up, which is the first time I have noticed it. Sometimes the light flashes; at other times it remains pinned to the driverboard.

Since the light came on, the car vibrates more noticeably and the acceleration is much slower.

I was wondering if anyone might have advice on the matter. Initially i thought it was to do with using Tesco fuel, but I recently refueled.

Thank you.
 
Hello can you give us more information such as what engine we are looking at? what age? miles ? from the top of my head it sounds like a coil pack failed on a petrol engine. cheers mike
 
Coil pack failure also causes substantial hunting of the engine at idle, is that happening with you?

If it is a coil pack failure stop driving it and get it sorted or you risk ruining the catalytic converter and possibly other things too.
 
Dear both,

Thank you for your replies.

My engine is a petrol 1.5cc, first registered in 2003 and it has 40,000 miles.

When I drove about yesterday, whenever I stopped the car smoke would emerge.

Does this sound like coil pack failure? Is it best taking it to Audi to repair?

Thank you.
 
Smoke could be from unburned fuel, so coil pack failure is very possible. Get it sorted, it isn't worth risking it.
 
Dear both,

Thank you for your replies.

My engine is a petrol 1.5cc, first registered in 2003 and it has 40,000 miles.

When I drove about yesterday, whenever I stopped the car smoke would emerge.

Does this sound like coil pack failure? Is it best taking it to Audi to repair?

Thank you.

I've got a 1.4 petrol myself and have had a coil pack go before, the symptom was an irregular misfire and stutter (not always present) but I didn't have anything else myself, e.g. no smoke or light that I noticed or remember.

I wouldn't jump to a coil pack conclusion, although it could be this. In any case, your best bet is to first have the car scanned as this will tell you what coil pack is faulty, if it is that. If you can find a member who lives locally and who has VAGCOM/VCDS, ask them kindly otherwise if you've ever up near St Albans let me know.

Anither possibility that springs to mind is a lambda/o2 sensor (which tells the ECU what fuel/air mix to provide and if it gets it wrong or is sooted up, it will turn on the emissions light, your fuel economy will reduce and you will likely burn rich, possibly making smoke. It can also put the car into limp mode in extremes).

As for whether you should take it to Audi, I would say that depends on your own competency, but I'd generally prefer a VW/Audi specialist over a dealer.
 
Emissions Light occasionally comes on on our 2003 1.4 SE Petrol. There is never any noticeable difference between when the Light is On or Off. It always goes away again by itself so I just leave it alone.

My experience of Coil failures is the Engine only runs on 3 Cylinders. Apart from last year when the RAC kindly fitted a Faulty Bougicord Non Genuine VAG Coil that made the Engine keep Cutting Out dead, even in the Fast Lane of the Motorway whilst passing HGVs.

Garages and the RAC could not diagnose it was being caused by a Faulty Coil. SCANS by the RAC and my trusted VAG Independant DID NOT FIND IT. So I would not go by that.

It was finally sorted out by good advice from A2OC Members on here telling me to fit a New Genuine VAG Coil. Never Cut Out again since ! The RAC did not even tell me it was not a Genuine VAG Part they had fitted. They even had the check to use the VAG Part Number on their Invoice to me !
 
Last edited:
Emissions Light occasionally comes on on our 2003 1.4 SE Petrol. There is never any noticeable difference between when the Light is On or Off. It always goes away again by itself so I just leave it alone.

My experience of Coil failures is the Engine only runs on 3 Cylinders. Apart from last year when the RAC kindly fitted a Faulty Bougicord Non Genuine VAG Coil that made the Engine keep Cutting Out dead, even in the Fast Lane of the Motorway whilst passing HGVs.

Garages and the RAC could not diagnose it was being caused by a Faulty Coil. SCANS by the RAC and my trusted VAG Independant DID NOT FIND IT. So I would not go by that.

It was finally sorted out by good advice from A2OC Members on here telling me to fit a New Genuine VAG Coil. Never Cut Out again since ! The RAC did not even tell me it was not a Genuine VAG Part they had fitted. They even had the check to use the VAG Part Number on their Invoice to me !

Just to add to this that I too had a faulty coil pack initially fitted and the misfire/ 3-cyl problem persisted, so as advised it is best to fit a genuine part. That being said, neither Volkswagen nor Audi actually make coil packs, so buying a decent brand is fine, e.g. Beru (which i think we're the original equipment manufacturer (OEM) anyway).

Lastly, there's been an assumption that your car has coil packs, but you may have the AUA engine, which had a single coil and distributor, not an individual coil per cylinder, so if that's the case it's a simpler thing to check. Still worth plugging the car in to find out.

Ps. '66Beetle - your emissions light is likely the pre-cat lambda sensor, you might not notice much difference initially, but your fuel consumption may reduce.
 
Back
Top