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MG MGF Technical - K&N in fog

Hi all,

Has anyone noticed a power decrease when you drive (with a K&N filter) in foggy weather?
This morning when I drove to work it was very foggy here in Holland and it seemed to me that the engine wasn't as lively as usual and throttle response was neither so good.
I've noticed this before when it was foggy, is there anyone who has the same experience?

I thought the engine would like cold damp air.

haven't driven in fog with the k&n thouhg so can't comment

Sounds like a very useful automatic safety device to prevent you injuring yourself (or others) through dangerous driving in unsuitable conditions.

Well done MG Rover/K&N - may I have one please:)

Ted Newman

I haven't noticed this Arend. If anything, probably the opposite (although not necessarily in thick fog). As Matt says, cold air with high water content should be denser, and therefore the engine's performance should be improved...

Rob Bell

Matt, Rob,

What I meant to say is that I suspect the K&N filter becomes "clogged" with damp.

I agree with you all that cold, damp air should be no problem for the engine itself.

I have notice the opposite, but it could have been that it tends to be very cold when foggy this time of year. I'm sure 'warmer' fog would have the inverse affect???


I dont think that will be a problem. K&Ns are used on motorbikes and jetskis where they are subject to a lot of water.

Bit more:
Completely unaffected by moisture
The K&N Flame Arrestor is completely unaffected by moisture, because of the unique oiled cotton gauze and epoxy-coated wire screen construction. So it's the perfect choice for every marine engine application, from totally race Jet Skis to dual carbureted Sea Doos to bone stock Wave Runners.

Of course if the filter was so clogged with filth then it is possible that any moisture hitting this filth could turn it into a sort of concrete and therefor coat the outside and prevent air entering.

Suggestion - clean the filter.

Ted Newman

I never had this problem, check your K&N is fitted properly as this could be an indication of something else.
Tony Smith

Sorry guys,
Tony, did you get my email, Fraser would like to talk to you?

Anyone remember carburettor icing in cold foggy weather?
Mike Cunningham

This thread was discussed on 10/01/2001

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