Car Failed MOT On CO Emissions Please Help

[BigDaveDJ90]

hello people
another problem with this vauxhall lump of fire fodder on my drive.

took it for MOT on wednesday, i thought a few things might of been a problem but never expected 2 pages of problems haha. alot of it is pathetic things like headlamp insecure and fog lamp not working. but then theres a fair bit of welding, and the emissions have failed, not as bad as i thought on the emissions tho as it only failed on CO levels.

the results are as follows:

Fast Idle Test: FAIL
CO Level 0.59% (Max=0.30) FAIL
HC Level 99ppm (Max=200) PASS
Lambda 1.022 (Max=1.030) PASS

Second Fast Idle Test:
CO Level 0.62% (Max=0.30) FAIL
HC Level 117ppm (Max=200) PASS
Lambda 1.018 (Max=1.030) PASS

Natural Idle Test
CO Level 0.45 (max=0.50) PASS

Sooooo the question is:

what will bring the CO levels down? as i dont know what it is related to.

any advice is good advice as im clueless.

thanks people

[projectredtop10]

Hi, could do with anything from a service to a good run down the road when was it last serviced? am a tester myself and seen cars with similar readings to yours, and 99% of the time it brings them down.

[BigDaveDJ90]

Well had oil change yesterday, I don't know previous tothat as I haven't owned car long but oil filter looked like it hadn't been changed since the factory and had plugs leads and fuel filter about a month ago, all plugs are fine aswell. Well it's in for retest this week so will take it for a good motorway run before then
cheers mate

[jordyp]

change the plugs mate that should help it.

[BigDaveDJ90]

Yeah forgot to mention it had plugs at same time as leads and that. Well I'll take it to garage and get them to check emissions before retest

[donnay1991]

Just like 5 mins before the MOT boot the car down the road. then take it in

[projectredtop10]

If you still have your standard air filter on just had a look at it. it cost next to nothing to change + helps emission, cheers

[BigDaveDJ90]

Well I've got a silly pipercross one on. Haven't got standard so I'll have to source one from a scrappy

[ashparky]

what enigine have you got? im also a tester and one thing i notice about a lot of old vauxhalls is that the breather pipes into the rocker cover get blocked up with gunk and if you clean them out it lowers the emmisions a lot. also make sure the car is red hot when it goes to be tested and give it a good thrash to clear any poo out.