This is my first post here so apologies if its in the wrong place!

I have just removed the air filter cover on my Focus  Zetec S and it makes it sounds a lot better! I currently only have the standard stock air filter in, and I want to make sure that it is okay to run the car with the air filter box left off?

My worry is water and other substances might be able to get in there, so if anyone knows more that'll be great!

 

Thanks in advnace!

It's not water that will be the issue, but heat.

The air box is designed to bring in a cold air feed. With no lid it will suck in hot air from under the bonnet.

1 minute ago, alexp999 said:

It's not water that will be the issue, but heat.

The air box is designed to bring in a cold air feed. With no lid it will suck in hot air from under the bonnet.

A fair amount of my friends have the open air filter set up and their cars have no problems.

I only do short journeys but I just want to make sure that I'm not going to cause any problems leaving it open.

 

Thanks

It will be ok to start with but few months down line you just gonna start creating problems, if it's sound your wanting nice roar go for induction kit

9 minutes ago, Damien said:

It will be ok to start with but few months down line you just gonna start creating problems, if it's sound your wanting nice roar go for induction kit

Doesn't the intercooler keep it cool anyway? Altough it will be bringing in more hot air without the cover, it'll still bring in just as much cold air.

ill follow any advice though as the last thing I want is to mess my car up

Thanks

Short journeys won't make a lot of difference, but once the engine is warm, you'll be pulling in more warm air.

As ambient air increases in temperature it becomes less dense, which means less oxygen for combustion.

The intercooler reduces the temperature as a result of the turbo pressurising the air and increasing its temperature. Intercooler performance is usually measured as a delta, which means if the air going in is hotter, then the air coming out will also be hotter.

The cooler you can make the intake air, the better. Cold air is more dense, so more oxygen available for combustion for the same volume of air.

Maybe you could get one of these -

http://www.knfilters.co.uk/mobile/mProduct.aspx?prod=57S-4000

There not my thing but think it would limit the amount of warm air being pulled in, give you the sound your after & piece of mind that the filters covered.