high emissions

[chilled]

high folks

i need to MOT a car that as been laying around for about a year
I have been told i need to drive it about for a week before the test due to high emissions
had the emissions checked and they are (CO 0.72% - limit 0.3% )
all the rest are OK

my question is do i need to drive it about for a week (if so how far)
or can i take it for a trip on the motorway before test (how many miles ?)
by the way the cat was changed last year

any advice would be much appreciated

Chilled

 

[bouncer]

Its obviously running rich, could be that it just needs to be at working temp. So a run down the motorway or even a good duel carageway should surfice.
Have you got the rest of the results of the emissions test, may be able to help some more. . . . poss.

sTeVe

 

[chilled]

hi bouncer
the results were

co 0.72 % fail
hc 110 ppm pass
lamba 1.02 pass
oil temp 112.8c ok

idle test
co 0.19% pass

cheers rocket

 

[rajinder_1]

try a good petrol (texaco ) and a good italian tuning should cure tha, or if you add some Forte gas treatment to the fuel

Raj

 

[Dieselman]

Give the car a good caning down an open road in low gear to heat the cat up fully. This should get it working properly again.

 

[television]

You are lucky in the UK, when living in Sweden the test are automatically dished out, numbers that end in an odd number go from 01-05 and even 06-12 for the test, mine was always early in Jan and often -20c the tester would have to drive the car out for a fast run in order to get the cars through.

Once I learnt this I could do a high speed run (120kmh) to the testing station and that worked fine.

 

[chilled]

thanks for the replies

i was going to give it a trip down the motorway for a hour the night before and the same again just before the test
from reading your replies that should do the trick

thanks again

Rocket

 

[television]

thanks for the replies

i was going to give it a trip down the motorway for a hour the night before and the same again just before the test
from reading your replies that should do the trick

thanks again

Rocket

Try and use a lower gear to keep the revs up, thats the quickest way to clear it

 

[chilled]

will do television

taking it for a MOT Friday will let you know how its goes
thanks everyone

chilled

 

[bouncer]

I would go with giving it a good thrash, get it nice and hot. if that doesnt do it then poss a lambda sensor faul. Or a small air leak in the system. Ecu tring to compensate for the extra oxygen just throws some more fuel at it. is the exhaust in good condition, before and after the cat?

sTeVe

 

[Dieselman]

The Lambda reading is weak mixture so any leak would need to be before the sensor.