Corsa Engine Management Light

[IanDB]

Our 1996 1.4 petrol Corsa has had intermittent problems with the engine management light coming on. About a year ago Vauxhall diagnosed this to be the exhaust sensor. However, everything returned to normal so we didn't get it replaced. Recently the light has started to come on after a few minutes driving. Question: is this likely to be the exhaust sensor again and if so, is this the unit that screws into the exhaust manifold at the front of the engine? I've half a mind to replace it just to see what happens as I was quoted "rather a lot" to get it fixed by Vauxhall.

 

[Spark123]

The reason for the management light coming on could be anything - the only way to know for sure is to get the fault code read off by a garage. Given the age of the vehicle you may find your normal back street garage won't have a lead to connect
If it is the lambda sensor it could be the one under the bonnet but could also be the one after the cat assuming it has a lambda sensor fitted here too.

 

[IanDB]

Spark123, thanks for the info. You're probably right about finding out exactly where the fault lies - another trip to Vauxhall. Out of interest, do you know how the lambda sensor works? Is it heat sensitive?

 

[Spark123]

Doubt they are heat sensitive given they are in the exhaust pipe, they don't work efficiently till they are up to temp tho. There is an explaination of how they work here: http://en.wikipedia.org/wiki/Lambda_sensor

 

[IanDB]

Excellent links, I've now learnt about lambda sensors. As this is an old car it looks as though this could well be the problem (they tend to pack up after 50,000 miles).

I might see if I can read the voltage output from the unit or just replace it anyway.

Thanks for the advice - much appreciated.