lube/ replace the cable would be my first port of call.

especially if it is open to the elements, routed under the bottom bracket.

HTH

Replace the cable and give everything a good clean and lube. My commuter front mech stops dowshifting about once a fortnight from all the road grime and I only clean it when I finally get bored of downshifting with my foot 🙂

Ta

have given it a blast with the hose still sticking but will drip some lube on the cable and rethread it. Its defiantly something in the mech thats sticking though just wont return

Sure it's the mech? Not very much to go wrong with a front mech tbh.

I had exactly the same problem and it turned out to be the shifter. Does the mech still stick if you disconnect the cable from it?

You can take the cover off most shifters (X9 in my case) and drip some chain lube on the mechanism. Be careful of all the small springs that'll try and make a break for freedom!

you can get mud packed into the cage/parrallelogram bit of the mech. Take the mech off, clean it thoroughly and lube it. May be worth bl;asting it with a hose to try and clear the crap out of it.

Thanks all!

RicB don't think its the shifter as the cable gets very slack, touches the tubing, when I shift down.
Will have to take the mech off of the bike and give it a proper clean see if that will do it if not then its a new one, can't complain about that though.

Ho HUM

If it's been sprayed with a hose, leave it on the bike and blast loads of GT85 into all the pivots and then manually force the mech in and out through it's entire swing until it moves freely.

As stated above, there's little to go wrong with a front mech and it probably won't need replacing unless it's really shagged.