I have a 93 Uno 1.1 I.E, with Bosch fuel injection.

The car has been laid up a few months, but started regularly and ran & drove fine. Now that I've tried to drive the car today, all of a sudden the accelerator pedal sticks to the floor!! And won't come back up when you release your foot, unless pulled hard by hand.

Seems on the throttle body, the pivot lever that the accelerator pedal cable fits onto won't move very well at all.

I tried spraying some WD40, on the pivot spring and lever but to no avail.

Not sure what to look at, or what to try as I've never had to fix or diagnose a fault like this. Is there a common part that fails, or something that needs cleaning or greasing?

Would really appreciate some help, as don't want to risk driving the car as it is.

WD 40 is a Water Dispersant, use a real penetrating oil instead.
Seems like a spring has broken, look at ePER on top of this page, to find out if there's a spring present.
Also, clean the inside of the throttlebody with carburetor(!) spray, to clean build up carbon, oil residu, gunk and sooth, that will prevent the throttleflap to move free.

After a bit of tinkering, I found the throttle valve position module was the culprit.

As it was stuck in the fully open position, I'd replaced this part previously as it didn't open!! Causing the car to stall, you can't buy this part from Fiat or Bosch anymore.

So I reluctantly bought a pattern part, hopefully should be in warranty otherwise I'll do a search on the net for a decent new or second hand Bosch unit.

It is still available here:

http://www.mister-auto.co.uk/en/search_s_refoem_0132008600.html

Thanks for that, might splash out and treat the car come pay day!!