Yes they can be cleaned, although I very much doubt it'll cause running problems.
Due to the nature of what they do, they tend to stay pretty healthy through out the cars life.
They all vary slightly between maufacturer!
I take it the Haynes book of lies covers nothing on the subject?
Try consulting Ford. Find a dealer with a service station tacked on the side and go straight in there. Saves dealing with the monkeys in the parts department

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Some people are like slinkies. Not really good for anything, but bring a smile to your face when pushed down the stairs!



From the moment I picked up your book until I laid it down, I was convulsed with laughter. Some day I intend reading it.