got my mot tomorow and i know my saph 1989 cossie runs really rich. if the mot wont pass it what can i do. is it safe to turn down the white co screw by the ecu then turn it back to same position afterwards.
cheers

 

Yes, just don't boost it up at all while you have it altered.

And measure the resistance of the pot so you get it spot on when you set it back

 

Why not let MOT station adjust it.
Cossies are easily capable of passing emissions test without this lowering nonsense.
Run it around 2.5% CO, and leave it, it will fly through emissions test and be ok.
tabetha

 

cheers

i think ill let the mot adjuast it if needed or it might even go through, then ill take it to a local tuner to get it on the rollers and adjusted properly, think its about time i improved my 13mpg,

tabetha are you saying the screw can be adjusted to 2.5 and left like that without needing a further adjustment and will be perfectly safe to use?

 

will be fine at 2.5% most cossie when set up are at 2.5 too 3% at idle

 

Yes 2.5% CO is perfectly safe and good, and MOT passable too, BONUS.
Anywhere between 2-2.5 is ok.
tabetha

 

Is the limit for non cat car 5% ?

 

cheers it passed straight through.mot tester said he didnt see any problem.