hi, i had the same problem, turned out that the idle control valve was sticking so cleaned out with carb cleaner . Youll find it on the throttle body held in by two screws.

hope this helps

sam

had similar issue, except car had just had new clutch and timing belt fitted, so was not looking for more costs.

So, my fix?. I looked at the throttle cable, and saw it was tight/ saw it was held in place by a spring clip, and basically moved it forward by 1 ring. This allowed the plunger to go to position A, and the ECU takeover throttle control (a quick clean with wd40 didn’t hurt)

The issue was caused by a bent throttle cable, shortening the cable length (just like if your foot was pressed on go pedal). If you look at the idle/stepper motor (Google image it) you will see that it's a sprung plunger. Foot off pedal, the plunger should be pushed back by throttle return spring (on carb (yes, i know its injection, but carb/throttle body)). Lets call that Position A (car at idle, ticking over). The ECU (computer/brain) detects this.

foot on pedal and this moves throttle, and plunger can then move (by its spring) to its middle position, where it normally sits and spends its life as you drive about, lets call that position B.

When you start car, the plunger is detected at Position A (pushed back, as your foot is off the go pedal) and the electric motor moves the plunger forward, passed position B to position C. This is actually the same as a choke (making the fuel "rich" and a dab of throttle).

Check you have the same amount of throttle movement fro the pedal (ie you can go “full throttle).

Looks like the cable got bent while in the garage. Could have been costly to id fault. This fix was free.