Sticking throttle - dirty throttle body or something more expensive?

Hi, I've got a 2000 4.6 that does not get used much, I'm located in Swindon. Just recently sometimes when you go over idle speeds the accelerator seems to get stuck and the revs don't die when you take your foot off of the pedal - a quick blip of the throttle restores normal operation.

However today all a quick blip of the pedal does is send the revs higher and they stay there and don't come down unless you repeatedly blip the pedal or pop the bonnet and yank the throttle/cruise cable a few times whilst the engine is screaming away beneath you. Obviously this is dangerous to drive and I need to sort it before it can go back on the road.

The car does this straight from cold but it will idle OK and will idle steadily all day long if you let it. On one occasion I could not get the revs to die down and had to kill the ignition at the key - it restarted again OK at idle.

The accelerator pedal has always been a bit jerky low down but I've checked the physical cables and they seem to be reasonably free and moving OK. The physical pedal travel seems OK in that it returns to the top of its travel fairly easily. I've done a search and found lots of stuff on TPS but my idle seems OK so I'm wondering if this is more a gunk build up somewhere that is physically making something stick in the throttle body area. Nothing under the bonnet has changed recently apart from a new battery (12v power kept on via spare battery and jump leads during change).

Should I try to clean the throttle body or is there something else to check/re-check first?

Can I clean the throttle body without draining coolant out as per Rave instructions?

It really feels like a sticky cable but at the throttle body the cable appears to move freely.

All suggestions welcome (including Burn it! That's what my Mrs would like me to do with it)

I had a similar problem I wd 40'd all the linkages and returning springs made sure they were all seated properly but and this is why I can't say what the problem was for sure I smelt burning by the fusebox and it was shagged really corroded and relay 6and 7 scorched so I ordered a new one and fitted it and all sorts of odd little probs disappeared including the odd throttle sorry not much help

Just got access to the throttle body and given it all a good clean with carb cleaner and gone over linkages with same and it feels a lot freer than it was. When I get more time I'll take the springs and things off of the spindle and give it all a proper clean. This is definitely where my problem lies as there is a lot of gunk on the spindles. It's good enough to drive now but with a little more effort I'm sure it will be as good as new.

Whilst I was there though I noted a drip from the throttle body coolant connectors :-( Time for a bypass?

Or buy a new throttle body heater plate - p38spares.co.uk has them...