Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Low CO emissions

Just had my Mog MOT'd and it managed to achieve a negative CO emission at fast idle!

Bet a LIFECar cannot do that!

Would that have an impact on your road tax?

I think road tax charges are based on manufacturer's official C02 data, which is not a mandated MOT test.

However looking at the following chart from Crypton it looks as if zero CO means the engine is running too lean.



My car has a Rutter sports exhaust and an ITG intake but no remap, it drives fine.

Does anyone think the CO figure is a problem? if so, what is the suggested fix?

the old fashioned check would be spark plug colour.. do they look like its running lean?

I tried to remove the plus previously, but even leaving WD40 in the well overnight they refused to unscrew. I don't want to apply too much force with the socket wrench in case I break the plugs.

Maybe I will leave them until I have to next visit a dealer!

Hi Clock, Forgive me if I'm teaching granny and all that, but WD40 really isn't a particularly good penetrating oil. Try some PlusGas. When it comes to undoing the spark plugs, I find a very high torque applied slowly is less likely to damage the plugs than a shock load - and of course a very close-fitting plug socket with the correct rubber insert is always a good idea.

Thanks Tim, I will try your method, always grateful for advice, much easier than learning the hard (expensive) way!

Hope it goes ok. This is of course the perfect demonstration of the wisdom of Cain's advice to whip the plugs out on an annual basis to ensure they don't seize up.

Ford engines seem to be slightly prone to this, the sealing around the plugs does seem to be less than perfect. On my Ecotec engine (Spanner Juggler reckons it comes from a Bedford Beagle) the coil pack completely covers and seals the spark plug wells, so no water can get in.

From my motorcycle days i always apply a good copper based anti seize past to my sparkplugs. Iv seen too many badly maintained old bikes that i have had the threads pull out with the old plugs.

Of interest my re-mapped sigma, was just on the limits for it's MOT. However when I checked the DVLA limit specifically for the Morgan, it transpired that it was well in. Seems some MOT stations are not aware of the adjusted limits.