MOT emissions Leon Sport

[Bluemerlin]

My leon sport (1.8t)has failed on emissions on the MOT.

On the first test, it was way off.

Fast idle CO 1.03% Fail
Second fast idle CO 1.03% Fail
Natural idle CO 0.59% Fail

I fixed the other failure items then took it for a good run just before the second test.

Fast idle CO 0.42% Fail
Second fast idle CO 0.42% Fail
Natural idle CO 0.05% Pass

As you can see it's very close. Any suggestions for getting it over the line. It's been serviced, but haven't done spark plugs. There is an advisory for rear silencer joint having minor leak of exhaust gases. Could that be the cause?

 

[Ash-Kennard]

go for an absolute blast (italian tune up) just before the mot.

what were the failures?

you running a sports cat?

Been mapped?

 

[Bluemerlin]

The other failures were ball joints.

I went for a blast before the MOT.

Standard Cat (Well i've not changed it)
Standard Map (Well i've not had it mapped)

 

[mattyholmz89]

Terraclean? Think that might do the job

 

[Bluemerlin]

Terraclean? Think that might do the job

Does that really work, always been dubious?

 

[andycupra]

what fuel are you running?

tescos momentum can help due to it having methanol? in it.

otherwise there are things you can buy to add to fuel for MOT tests.
as you know make sure the car is properly up to temp. cats work only when at proper running temperatures.

 

[mattyholmz89]

Does that really work, always been dubious?

Search forum mate few debates... One thing is clear it drops emissions down and makes for a smoother quieter running engine that's what I would do first anyway or get it on a private patch of road and hammer the holy hell out of it...