Air filter cover

I had the same problem and it was a severe pain (especially in the fingers I pinched with the pliers) after the dealer said it would cost $200 to replace the whole box on 2001.

Best thing to do would be soak the bolts and nuts with a penetrate. I would think a pair of good size needle nose pliers with a 90 degree bend would be best. There is room to grab the nut, but not much. I did it without this kind of pliers but next time I am getting a new pair of pliers.

Good luck.

Thanks for your help. I suspect its a common problem from the shape of the nuts.

In alt.autos.ford.focus Pajtas :

I suspect it's primary a problem from people just tightening bolts far to close?

No, it is a really crappy design. The nut has a serrated edge that is round and is pressed into the plastic base. The engine compartment is a very hostile environment for any kind of metal object.

I would advise anyone who checks their air filter to lube the nuts and bolts everytime they open the box.

So the bottom of the circular "nut" is serrated towards the base of the plastic airfilter cover? Therefore if I oil the screw and apply pressure between the nut and the bottom airfilter cover it may catch and allow me to take out the screw?

Yes and is imbedded in the cover.

Therefore if I oil the screw and apply

Part of the nut is exposed and you should be able to grab it with needle nose pliers.

In alt.autos.ford.focus EOO :

Zero problems here on my 1999 Focus with the air filter cover.

Good advice, can't hurt in any case. If you are in addition a little careful while tightening bolts one should be fine.

I had trouble getting mine off first time. I removed the box from the engine bay and used a combination of penetrating oil and mole grip pliers to get it undone. Then applied copper grease to all the threads and not been a problem since.