My 2003 focus went in for a service yesterday. One of the things they picked up was that both intercooler hoses are split and leaking oil.

First of all why would they be leaking oil. I thought they would just contain hot gas.

If the intercooler is the large rectangular object right at the front of the engine bay, are the hoses the 2 short rubber hoses on each side. If so it looks like a fairly easy job to do. They've quoted me £180 to do it, which I can't understand. Am I missing something?

there could be other hoses that have a split. best bet is to get the engine running and pour some soapy water over the hoses to see if any bubbles appear - this will tell you where the splits are.

if they are easily accessible then change them yourself - preferably for silicone hoses if you can get them at a good price.

a lot of intercoolers/pipes get some amount of oil in them - its ones of those things.

I'll give that a try. Thanks for your help

So I did what you suggested and there is indeed gas blowing out from the ends of both intercooler hoses. I tried tightening the jubilee clips but it hasn't cured it. I guess the hoses are too old and compressed to form a good seal.

It looks like a fairly straightforward job to replace them so I'll get some and do it myself. How that garage could justify quoting £180 I don't know.