Emissions Light On A 2008 Vauxhall Corsa

[Tefler]

The emissions light came on in my Corsa in January. I took it to the garage, where it was checked, and I was told they could find nothing wrong but to bring it back if it happened again. It did last week (mid-September). I took it back and was told that it was a sensor in the exhaust pipe which was faulty. It will cost several hundred pounds to sort out, but not to worry if the light didn't come back on again .... which, inevitably, it has, just a few days after it had been turned off.
The mechanic said that, as it was a faulty sensor and not the actual emissions which was a problem, I only needed the sensor replaced if it was too much of an irritant, but how do I know if there is actually a problem with teh emissions? Any advice?

[gingejbee]

Are you due an MOT soon? If the emissions really are too high, you'll soon know ...the car will fail. Of course, you could go to a suitably-equipped garage and have the emissions tested.
On a previous car, the engine-management light came on a few times and when I phoned my dealer, the workshop manager suggested that I take the car on a long fast road to get everything really hot. I did...and the light never came on again, right up to selling the car three years later. Worth a try?

[tonyav]

I'm guessing that the sensor that the mechanic is talking about is the lambda / oxygen sensor ( if there is a fault with it your engine management light will come on ).
Looks like this
http://www.vauxhallworldparts.com/images/0258005291.bmp

I'm assuming that it was a Vauxhall main dealership that quoted you several hundred pounds to fix it. It shouldn't cost anything like that at a local garage, the part it self doesn't cost very much.
http://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=p2050601.m570.l1313.TR0.TRC0.H0.Xlambda+sensor+2008+vauxhall+corsa.TRS0&_nkw=lambda+sensor+2008+vauxhall+corsa&_sacat=0

[Tefler]

Thank you for your responses. I'll be doing some motorway driving soon, so will be able to try gingejbee's idea. If it doesn't work, I'll see what a local garage can do for me, Tonyav.