My engine exhaust warning light is on, amber, in my 2000 VW Beetle it was MOT-ed just last month and passed is it just a sensor issue or is it more serious?

what is the code coming up? when was the last tune up? how is the air filter? are all the tires set at the right psi? what is the make and model?

could be but i suspect the wires on the lambada sensor or the lambada has packed up`,get someone to plug it in and read the lambada temperature readings

Malfunction indicator light it is the symbol of your engine with a line of suffering and the word "CHECK" -- this could be something minor like needing a spark plug to be replaced (common problem) or to something more serious like engine electrical work needed. a flashing engine light is the more serious so you are not to worry.
keep this handy: http://www.newbeetle.org/forums/2-0-liter-gas/39141-where-can-i-find-warning-light-diagram.html

check the plastic connectors in the cooling system.vw is notorious for the plastic stuff cracking causing a slow leak

sorry if that is the code it is not correct with the obd format it surpose to have something like P0033 re-check and let us know the correct code

check your oxygen sensors .

No,clean or replace the exhaust lamda sensor

its your secondary air pump. it turns on in the cold morning to inject more air into your exhaust, something about emission. its normal to be high pitched. once on my car it was way loud, i looked and the hose had disconnected. either way its normal if its not super loud. but if its everyone is looking at me loud then check for loose hoses!

I bought a 2000 polo 1.4 yesterday after having an MOT. The warning lamp came on today but the car is running fine. Whether its the Lambda sensor or just the light itself is a common fault, I think garages turn off the lights to get it through the MOT then they come on again in a day or two!

go to autozone and use there code checker and it will tell you whats is rong