Emissions warning light...

[sparey]

Just wondering if any of you have had this, my emissions warning light comes on every so often then stays on for a few engine starts then disappears for a bit before coming back on etc. From what i've read i think it may be a faulty lambda sensor or something which costs about £200 to put right at the dealers. Is there any way of turning the light off as there is no difference in performance (what there is of it in a 1.2 55ps ) and i don't really want to spend any more money on the car as i've spent loads on it recently.
Any help would be appreciated
Matt

[Rich_T]

Was told when i had my light on it was probably an exhaust sensor faulty, so booked it into vw and they told me they didn't really know why the light was on, maybe my non genuine dump valve was the cause, which had been on 12months or more, so they reset it and charged me £45

So it could be the lambda sensor, when i priced one up for mine it was about £55 or so from a motor factors

[aaronon]

I have the same car as you, when mine comes on I notice petrol consumption gets a whole lot worse.

I've had mind come on twice.

One was for a faulty bit of wiring (£20), and the other was because the o2 sensor was dirty (£20 to clean it).

[RUM4MO]

I have the same car as you, when mine comes on I notice petrol consumption gets a whole lot worse.

I've had mind come on twice.

One was for a faulty bit of wiring (£20), and the other was because the o2 sensor was dirty (£20 to clean it).

It does sound like it could be the first O2 sensor - needs a scan to prove it. If it is, it will quickly become a permanant failure and will be an MOT failure, cleaning them is not really very useful or effective and mainly its the heater circuit that has failed. If I were you, I'd find someone to scan it - even a £40 Gendan VAG scan tool will identify it, if its bank1 sensor 1 just buy the real one from VAG, get an open ended spanner and replace the probe.

[dts]

I'm a new Polo TDI 130 owner but i've had some experience with my girlfriends Polo 1.2 9n3 with this emissions problem. It's not always as simple as a sensor replacement, here is the possible causes which are all the things my girlfriend had had done before finally curing it.

Brake pipe split - runs between the servo and cylinder, it splits right at the join with the nipple so you need to take it off to inspect, if it is split at the end it lets air in and brings up the same fault code as a sensor would, you can trim this off and reconnect it without buying a new pipe.

Lambda sensors - Both these will need replacing if the above doesn't cure it.

Cat convertor - Expensive but cheaper than the final option

Valve seats - these can become worn on high milage, girlfriends 05 car has done 81k from new and this was her problem, they need taking out, head off etc, seats recutting.

Hope this helps.

[K.I.T.T.]

I'm a new Polo TDI 130 owner but i've had some experience with my girlfriends Polo 1.2 9n3 with this emissions problem. It's not always as simple as a sensor replacement, here is the possible causes which are all the things my girlfriend had had done before finally curing it.

Brake pipe split - runs between the servo and cylinder, it splits right at the join with the nipple so you need to take it off to inspect, if it is split at the end it lets air in and brings up the same fault code as a sensor would, you can trim this off and reconnect it without buying a new pipe.

Lambda sensors - Both these will need replacing if the above doesn't cure it.

Cat convertor - Expensive but cheaper than the final option

Valve seats - these can become worn on high milage, girlfriends 05 car has done 81k from new and this was her problem, they need taking out, head off etc, seats recutting.

Hope this helps.

Very informative first post!

Welcome to UK-Polos!

Ash

[dts]

Cheers Ash, i think i should offer some more advice on this one because i know it can be a very common problem with the three cylinder engines especially.

The brake servo pipe is around £30 so if you get away by cutting it back and refitting it's good, i know it sounds silly but i really would recommend doing this before trying anything else.

Obviously you will need to get the fault cancelled off with a vagcom after each try, if you dont know anyone who can do this for a favour or a bear then i find you can take it along to your local inandout or quick fit and pretend to them you know nothing, they will on most accounts tell you it's the cat convertor but will reset the code for you if you ask them for free, if you say something like "can you reset it for me and see if it comes back on and then i'll come back for a cat", get them to quote you for a new cat and go on your way. If you have to go to stage two, lambda sensors, buy them and get an independent garage to fit them for you, dont pay dealer prices unless you really can afford to throw money away. At this point the garage that fitted the sensors will reset the code again and away you go.
If it comes back on then its most likely a new cat, buy one as cheap as possible but try and get a gen part, they last longer and thats why they cost more.
Again, reset by garage and away you go.
If this has not cured it then it's trouble time, the head off and valves cutting etc will cost £500 even if you do it yourself with the kit and parts alone.

I hope this helps, if anyone is going through this problem feel free to contact me and i'll advise best i can.

Jay.

[sparey]

i'm going to get it looked at later this week, not had time to take it yet, just gonna get the code read first so i've got an idea of what the problem might be
but thanks for the info hopefully its nothing too serious as is only done 35k

[RUM4MO]

The comments I made about getting this car scanned before doing anything else still stands, there are many fault codes related to the Lambda probes and quite a few of them will point to the probe being faulty, as opposed to making a generised "lambda probe problem" - as long as you use a VAG specific scan tool.