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MG MGF Technical - High Carbonmonoxide valu


In Sweden we have quite restrict rules how much "Co" the cars exhaust fumes can contain. Now my MGF exhaust fumes contain too much. Do anyone know how I do too lover my "Co"-value?
How do I adjust the carburettor? Is it enough too change oil, oil filter and air filter?


>How do I adjust the carburettor?
you dont, the F is FI
>Is it enough too change oil, oil filter and Air filter?
changing the air filter may help if it is clogged.
>Do anyone know how I do too lover my "Co"-value?
General advice is to take the car for a long hard blast and then get them to check the emissions straight away, cat's only work when they are hot, newer cats (as in newer designs) get up to temp quicker and so need less running of the engine. Speak to the test centre about doing the test at a known time (don't let the car sit) and you will probebly be fine.

If this doesn't fix the problem then it might be the lamda sensor, or possibly the cat needs replaceing, but don't even entertain this until you have had a hot retest (and don't take their "we reved the engine untill it was hot", make sure you do it)

Will Munns

Took my F for its MoT today - glad to say it sailed through again. Which made me wonder - my car has done approaching 67k miles, and is 7 years old. How much longer can I expect the cat to continue performing adequately?

As it happens, I did take the car for a quick blast around the North Circular before pulling into the testing station for the reason that Will mentions above: a nicely warmed through catalyst will perform a whole load better after a good thrash through the gears to the red line than a cold cat that has been 'choked' by numerous short town journeys.
Rob Bell

Glad to hear you news Rob!

I confess ours is due its 5 year MoT in December (last one, not next....) and should perhaps get this done!

Judging by the lack of adverse feedback, the F seems very gentle with the CAT.


Patrick Beet

The Cat doesn't have to do much on a K series: there are tales of people getting through the MOT without one at all (byepass pipe)...

Mine's had trouble with a track rod end and a bottom arm bearing this year, and will be needing some front disks soon too... I guess they're things you've "upgraded", aren't they, Rob (I presume at least that Techspeed checked them!)


Thanks for all tips, hope I will get thru the MoT next time.


Rob, i had a pug once that needed a new cat after 230k km, but not fot not coming through MOT, but falling apart.
It should last a bit longer.

Johan Slagter

That's encouraging to hear Johan!

Neil, I've had no problems with the swivel ball-joints, but the track-rod ends on the end of the steering rack were, of course, changed when I had the steering rack swapped to a TF item ;o)
Rob Bell

My old F once failed it's MoT with high emissions caused by broken lead from Lambda sensor.

The break had occured because of rubbing against the manifold heat shield.

Fairly easy to spot and fix with 'engine cover ' off.


ps Of course if you pick the right pipe on a TF it will never fail so long as you've not disabled the exhaust shut-off valve :-)
John Thomas

This thread was discussed between 19/02/2003 and 25/02/2003

MG MGF Technical index

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