it'll be the idle control valve


one the side of the inlet manifold, looks like a tube about 6 inches long with one side being a bit thicker than the other and with 2 wires going to it on a multi plug

will be held in place by 2 10mm bolts top and bottom

it will need cleaning at the very least by letting it soak in a bowl of petrol overnight, just don't get it into the electrical contacts but make sure it goes into the 2 holes and you let it sit for about 24 hours

you will need a new gasket when you refit it

new ones were about £50 last time i checked