MOT failure - Lambda sensor?

[gofasterrosssco]

My cappuccino just failed its MOT for emissions on the fast idle part. The mechanic suggested a new lambda sensor might help as it just failed.

Any opinions......?

Thanks

Ross

[numbnuts]

Take it out and clean it with a wire brush, chuck some fuel system cleaner into the tank and change the air filter.
But before you do all that give the cat a thump with your fist to make sure its not all broken up inside

[nighthawk]

I'd also suggest cleaning the sensor, but use a carb cleaner while the sensor is unplugged....(the heater element ignites carb cleaner!)

Then after a good run to get the cat flushed through take the car back for a retest making sure it's still as hot as possible when they retest it

[andys2]

If you do need a lambda, try these guys:-

http://stores.ebay.co.uk/MIDDLESEX-TU

I just got one for my Audi S2, I asked them which one I needed and got an e-mail back straight away, placed my order and it came the next day, all for £43. Genuine Bosch sensor too.

Andy

[GreenV8S]

Have you ever successfully cleaned a lambda sensor? Given how fussy they are about contamination, I would have thought you would be almost certain to bugger something up. I've never bothered trying to clean mine, just replace them. If it's a narrowband sensor (I assume it is) you can get an indication of whether everything is working by monitoring the voltage output. If it is cycling about once a second or faster, everything's basically OK. If it's slower it worth replacing it anyway. If it isn't cycling at all something's wrong, could be a duff lambda sensor but could also be some other fault, time to ask the ECU what it thinks is wrong.

[Tony427]

A full bottle of fuel injector cleaner in a quarter of a tank of fuel, thrape the bejeeebers out of the car for half an hour or so, and you will very likely sort it out.

Cheers,

Tony

[stevieturbo]

Must say, thats the first Ive ever heard anyone suggest cleaning the sensor !!!!!

Check it, or replace it.

[eliot]

I would say avoid trying to clean the sensor, will almost certainly knacker it.

try www.justlambda.co.uk/ also.

[911mot]

What were the emissions readings?
CO too high or lambda too high?
If its lambda check for a hole/blow in the exhaust