Fiat brava 1.2 1999
I recently sent my car in for its NCT (irish equilent to MOT). failed on a few things like tyre which where all easy to fix. But i underestamited the emission fail. So far i had a new front pipe to my exhaust thats fixed the lamda reading, which is great. But i also had all the usual stuff cleaned and then a new cat converter. The gaurage told me that is was now perfect. true the car sounded lovely for the 1st day. Anyway the car failed it RETEST on EMISSIONS. :bang: Of course i was stressed. so i went back to the garage and they couldnt believe it. Anyway they believe something has gone after they fitted the cat. They even pop a second cat on to see if it was a dodgy cat and still the emission are all over the place. they tried a o2 senser, no joy. Now there having to try a map sensor. Does anybody have any ideas?

just to note my rev keep going up and down so that why there trying the map sensor.
just a wild guess could a faulty alternator that not charging right be interfering with the ECU and therefore effecting my rev thats causing bad emission? Like i sad a wild Guess.

Sounds more like a dirty Air Flow Meter to me, I think there is a guide for cleaning one either on here or www.fiatboo.co.uk

Ok the map sensor didnt make any real difference. I mentioned to the mechanic about the air flow meter sensor and he told me there isnt one on the 1.2 model. so am at a dead end at the mo.

Does anyone know if a faulty ECU could cause the erratic rev andthus send the emissions off? if so is it worth picking one up from the scrap yard and whats a good price to pay?

fill it up with v power an thrash the balls off it often works