First post and need a bit of input please.

Apologies if answer is on another thread-have searched-but can't find.

Warning system has come on identifying-engine systems fault.

Main dealer has diagnosed as faulty throttle housing-they have 'cleaned it up' and say car can be driven for a while-but warning message light stays on-and am advised it will need a new throttle housing .

This apparently at main dealer is £500 !!

had a few cars (not fords before)-but never had this fault before-and know nothing about it.

can anybody shed some light on it-maybe direct to another thread-and give guidance as to whetherr there is an 'alternative' cure-and'or if the cost of £500 is about right !!

many thanks