Poor Emissions (from car)

Ok MOT day today and it failed on emissions

CO

should be 0.30 Mine 4.46

HC

should be 200 Mine 355

Lambda

0.97 1.03 0.897


Any ideas what could cause this? I know it could be a faulty Lambda sensor, but any other ideads? cat seems fine from outside... I have a Sportex Cat back but that shouldnt make a difference.

Thanks

i know if a car has stood for a while it can affect it, if so take it for a long run.

Thanks buddy, but the car is used daily on long trips... ty

Hmmm apart from a faulty lambda, i know old spark plugs can give you poor emissions.

Hi,
The list is long: poor spark plugs/coil(s), blocked air filter, poor compression, faulty lambda, ECU, sensors, injectors........
Suggest full service and test compression and also test lambda see http://www.picotech.com/auto/lambda_sensor.html
and
http://www.lambdapower.co.uk/
Good Luck

It COULD be anything... but change the Lambada probe and enjoy a new world of emissions-reduced motoring.


Ralf S.

Thanks for the response guys, I checked one of the websites that Tim sugested and checked the lambda plug and that seems to be fine, also checked the spark plugs a few other things, got it booked in to have a new Cat tomorrow morning, so hopefully this will sort it.... will let you know.

Jack

I'm gonna go with cat is fubared. They don't last forever

Well just replaced the Cat for the sum of £129 , and the emissions are still very high, it has reduced them a little but not enough to pass an Mot, Just looked up the Lambda sensor again and its a universal one, not a model specific one, so thats going in the bin and just ordered one for £55 from Rapid....
This is an expensive year for my car, what with new radius arms, exhaust, brake system and other misc things going wrong, at the moment im a very sad Fiat owner

Oh that sucks, remember to reset the ecu once you fit the new lambda.

I would of forgot!!, Ace thank you.... Just have to work out how to Set up the Toad Alarm once the batterys dead

Just replaced the Lambda, and the batteries been disconnected for an hour now.... When i reconnect the battery, should i start and leave the car to idle for 5 mins for the ecu to figur out its tricks? or take it straight for a normal drive for 1/2 hour?

Iv been told different things?

Usual procedure is to let it idle upto temp (until the fan cuts-in), then go for a gentle 5 mile drive without using full throttle if possible to allow the ECU to learn the basic parameters using the Lambda/ knock sensor readings.