hi guys got m.o.t on fri
i took it for a emissions test results were 4.87%
is this purely because decatted and chipped ?
or ive read possible faulty lambda sensor ?
any of you guys had this prob is there a quick fix ?
any info muchly appreciated
thanks

 

You will always struggle if you have a full decat, but your co level is way off the chart!!

Could be faulty maf, lambda, wrong spark plug gap. Car is majorly over fuelling, don't think even if you car had both cats you would get the co level low enough.

Check for fault codes on your ecu.

At my last MOT car was 0.45% fully decat or 0.27% with the cat on

 

thanks 4 reply m8
ive just checked previous crypton gas analysis paper. results on that were 0.30 and car had same mods as now but diff induction kit !
would it make any diff putting a std airbox just 4 the m.o.t test ?

 

Air box could make make a difference, but not that much.

Something has been changed / gone wrong since the last MOT

 

What about HC level?

 

the guy at station only mentioned co and looked underneath car and said no cats ! he didnt seem 2 know a great deal which doesnt help because neither do i !
what are all the levels and what roughly should i be getting ?
car runs great never misses a beat gives me 200 + miles 2 a full tank never had cel light on ive had temp sensor done and waterpump in last few months

 

If your Lambda sensor is in any way faulty, this could affect your fueling at idle and cruise.