HELP MOT fail on emissions...imagine eh?
 

Hi All

I'm in the uk and my '04 192 has for the first time failed the MOT on emissions by a considerable amount (CO>0.2% i got 2.9%)

I had no engine warning light on so that kinda number points to a misfire. Plugs are only a month old and air filter 3 months so i dropped the oil (again!) replaced the filter, HT leads and the coil packs. I also gave it some stp to shift a bit of carbon along with a razz up the motorway.

Anyhow long story sort it looks like the cat converter is very nearly dead and so i've ordered one and i'll replace it tomorrow. What i need to know is does anyone have an idea what 02/lamda sensors i need for pre and post cat and also where i can get them from and I'm talking cheap as possible (can i use generic?)

cheers all

If you replaced the wires and coil packs after failing your MOT, you might want to go get that retest before you spend the money on a new catalytic converter.

Chances are with those bits replaced, you might bring the CO emissions down enough to pass the tests. What was your CO2 readings, if they gave you that in your results?

BC.

If its the original cat, your doing well for it to last this long, I would have replaced that first before the plugs, considering their just 3 months old ,any how, there are many posts on O2 sensors, the search icon is your friend.

Did you get your problems sorted out?? My '05 just failed on CO readings, about to go and pick it up now but don't really have a clue where to start...there are so many possibilities with emissions.

actually this car is pretty simple for emissions. it really only has one emissions part the cat, just like every other car.

so step 1, fix any check engine lights
step 2 is to check the ignition, it needs to work. i just use a timing light, i check each of the 4 wires.
step 3 is to pull the cat. there are two bricks, one you can see from the front, and the second you need to remove the o2 sensor to see.

if you have an engine that is running ok, and a good cat, it'll pass easily. if you don't have a good cat, you will be way off

Yup it's pretty much always going to be the CAT, i put an after market one on that i got off ebay. Only problem was i then had the pre CAT O2 sensor fail a few months later (expensive no matter where you look!)

So my car has been sat in the office car park, gathering dust until i A) Scrap it! B) Convert it to a track car and buy a trailer.

Well luckily it wasn't the cat for me, was the rear O2 (lambda) sensor. The direct fit ones are expensive, I got a generic denso one and soldered it to the original multi plug.
Fixed for 40 pounds plus a little time.