Exhaust Warning Light - 2003 Polo 1.2

jackb · Post by **jackb** » Mon Nov 03, 2008 2:58 pm

Hi Everyone.

I bought a 2003 1.2 Polo as a first car about one week ago. I was given a good price because the exhaust warning light had come on and they did not want to have it repaired.

Since then, the light has gone off. I have been driving quite a lot over the last few days (as you would expect from someone who has just got a car for the first time!) I have been mainly in the city, but yesterday - as I was on the motorway - the exhaust warning light came back on. Any ideas what this could mean? Could it be the catalytic converter or lambda sensor, and are these expensive to replace?

To complicate it further, I've read that quite a lot of VWs / Polos have issues with warning lights, so I'm not sure whether to leave it for a few days to see if it goes away, or take it to a garage right away. I don't want to damage the car by driving it if there is a problem, so I'm in a bit of a fix.

Hope you can help.

Jack

RUM4MO · Post by **RUM4MO** » Thu Nov 06, 2008 1:11 pm

Firstly, I think as you have a 1.2 engine, you'd be better off (get more/quicker replys) moving this to the Polo MK6 section of this site.

Now warning lights that come on then go off, first thing is that if a fault is logged within a specific controller, that controller will switch on threvevant warning light - in your case engine management light. If that fault was spurious - ie appeared then disappeared, then if it did not appear again, then the dashboard warning light would be put out after 6 > 8 engine starts later. This seems to be what is happening to you - so it could be that there is a re-curring engine problem being sensed.

Until you get the car scanned and the faults cleared, you will not know what exactly is the problem - so you could end up just changing things. The problem is that you have mentioned Lambda probe and CAT - that might be the very reason for these faults - I take it that you have read up on this engine's probable problem areas, if not then take a look on www.seatcupra.net (Ibiza 4L section) and www.briskoda.net (Fabia section) as I seem to remember this problem has been covered before many times - maybe even on this site - but its better to get fully loaded up with as much info as possible. Do you not know anyone locally with VAG-COM?

chewy · Post by **chewy** » Thu Nov 06, 2008 1:46 pm

When this light came up on mine it turned out to be the EGR valve

RUM4MO · Post by **RUM4MO** » Thu Nov 06, 2008 3:45 pm

chewy wrote:When this light came up on mine it turned out to be the EGR valve

Yes, that seems to be the other usual possibility - so jackb I'd do as I suggested and get together all the facts - or just find a guide to getting the EGR valve out and its pipe work and clean up both parts as that would be a cheap possible fix!

jackb · Post by **jackb** » Thu Nov 06, 2008 5:14 pm

Thanks for the tips. I went to an independent garage who read the fault code for free. They said it was most likely the Lambda sensor, but they weren't totally sure. They deleted the fault and told me to wait a few days to see if it comes back on. Thanks again.

RUM4MO · Post by **RUM4MO** » Fri Nov 07, 2008 8:27 pm

Lambda probe? My wife's 1.4 16V Polo had a problem with probe S1 - the precat probe, listed faults were a fault with the referance voltage and a heater problem, if this is what was logged with your car then it is almost certain to be the probe - they cost Â£109 + VAT and are quite easy to fit. This fault appeared and I cleared it, it re-appeared a week later cleared it and it re-appeared at the next engine start. So I ordered a new one, they tend to be made by NGK and traded under their sensor brand of NTK, you can buy a new one on-line but if it is the real thing with the correct length of cable + protection + connector, then you are just as cheap to buy it from a VW garage.