Failed Mot Emissions

[dylbachgti 0]

205 failed mot yesterday on emissions any ideas its running to rich shoul be a bout 200 co its up 680 co havent got a clue how to adjust any help would be great thaanks guys

[welshpug 1,657]

Hi Dyl, what does it say on the sheet for the CO % and HC ppm?

[rallysteve 22]

Could be a few things causing the problems. Without seeing the HC reading its hard to pinpoint. If HC is good then it is a fuelling problem i would imagine. Most simple thing would be blocked air filter but could be things such as AFM.

 

Will try and help more with more info

 

Cheers Steve

[DamirGTI 342]

If it's a 1.9 , take a look on top of the AFM , you'll see allen screw inside the hole on the AFM body (some might still have plugged hole with cap though , if so just remove it in order to access the screw ..) take the allen key turn the screw all the way inside as far as it goes then back it up counting 7 to 8 turns from fully inside and stop there .. then try the sniff test again .. if it still wont be enough for passing , back up the screw 2 or 3 more turns out .. if the problem isn't in the AFM spring tension calibration or some engine management sensor malfunction this the AFM mixture screw tweaking should do the trick

 

Damir

[dylbachgti 0]

If it's a 1.9 , take a look on top of the AFM , you'll see allen screw inside the hole on the AFM body (some might still have plugged hole with cap though , if so just remove it in order to access the screw ..) take the allen key turn the screw all the way inside as far as it goes then back it up counting 7 to 8 turns from fully inside and stop there .. then try the sniff test again .. if it still wont be enough for passing , back up the screw 2 or 3 more turns out .. if the problem isn't in the AFM spring tension calibration or some engine management sensor malfunction this the AFM mixture screw tweaking should do the trick

 

Damir

 

thanks i didnt get a fail sheet just go home change the bottom arm and try and do something with the emissions but i so it on the comm p it was sky high ive tried to adjust that mixture screw is there any way of knowing without putting it on a probe , fitted a new green cotton filter and new sparkplugs due to the old filter a bit s*itty,

[mr_exe 1]

I find changing the oil helps if its been running rich as there will be traces of petrol in the oil.

[JonnyB 1]

Try this:

 

http://forum.205gtidrivers.com/index.php?s...422&hl=ohms

 

Hope it helps...

[2-Pugs 57]

Mine failed MoT on emissions last year, I fitted a new coolant temperature sensor, worked a treat, brought the emissions back within range.

[dylbachgti 0]

Mine failed MoT on emissions last year, I fitted a new coolant temperature sensor, worked a treat, brought the emissions back within range.

 

fantastic will buy a temp sensor tomorrow thats the joy of staff account he he anyone any clue of a part number??where is it on the car?

[rubyna 4 1 Cars]

fantastic will buy a temp sensor tomorrow thats the joy of staff account he he anyone any clue of a part number??where is it on the car?

 

Do a search for the part number theres been about 100 threads on it.. Hope it sorts your probs..

Luke.

[Bogsye 22]

It would definitely be worth checking the resistance of the probe at various temperatures. Take it out and pop it in water of a known temperature and see what it gives - definitely worth the hassle incase you end up throwing money after something that works. If you do a search you'll find the resistances.

 

Others may know better, but I also understood that on an open circuit on a sensor the ECU defaults to a hot/summer value. So if the engine is warm, but running rich, then I'd imagine if you pull the plug then it should run better/leaner if it's the coolant temperature sensor that's faulty.

 

My emissions issue was a duff oxygen sensor. Not sure if your car is a later 1.9 with a Cat? If some sod hadn't pulled out the KAT bulb on the dashboard I'd have discovered the fault more easily.

[welshpug 1,657]

I'd check it with a Multimeter first Dyl, also getting an idea of what the emissions actually were would help point you in which direction to adjust or replace stuff, the limits are 3.5% CO and 1200 PPM on the HC, they run best at 1.5%.

 

if its not a million miles out on the CO I would turn the Allen screw on the AFM in a clockwise direction, don't go too mad though!

 

Like Damir said above, wind it all the way in, then 8 odd turns out, that'll give you a starting point.

 

Pob lwc!!

[dylbachgti 0]

I'd check it with a Multimeter first Dyl, also getting an idea of what the emissions actually were would help point you in which direction to adjust or replace stuff, the limits are 3.5% CO and 1200 PPM on the HC, they run best at 1.5%.

 

if its not a million miles out on the CO I would turn the Allen screw on the AFM in a clockwise direction, don't go too mad though!

 

Like Damir said above, wind it all the way in, then 8 odd turns out, that'll give you a starting point.

 

Pob lwc!!

its runnong at 6.5 co new coolant temp sensor new plugs and new air filter tried to adjust mixture screw its running beetter now and not fouling the plugs after i changed the oil this afternoon 5 w 50 motorsport coma oil will c friday afternoon im crossing everything

[dylbachgti 0]

Do a search for the part number theres been about 100 threads on it.. Hope it sorts your probs..

Luke.

car passed thank you very much everyone

[davey205 7 1 Cars]

If it's a 1.9 , take a look on top of the AFM , you'll see allen screw inside the hole on the AFM body (some might still have plugged hole with cap though , if so just remove it in order to access the screw ..) take the allen key turn the screw all the way inside as far as it goes then back it up counting 7 to 8 turns from fully inside and stop there .. then try the sniff test again .. if it still wont be enough for passing , back up the screw 2 or 3 more turns out .. if the problem isn't in the AFM spring tension calibration or some engine management sensor malfunction this the AFM mixture screw tweaking should do the trick

 

Damir

 

Does the same go for the 1.6 ive been looking at my afm and its just really crudely glued on im sure someone has had a fiddle in the past