vacum on tb

[Aragorn]

right ive done this and wrote the guide so here goes:

the 1800 TB has a throttle stop screw on it which as it comes off the cav is set too high and will mean it will idle very high (over 2k iirc)

if u look closely at the linkage you'll see it comes down against a screwed rod, on the other end of this screwed rod all u can see is a metal blank, prize it out with sharp thing and u uncover a screw, wind this screw back untill u get sensible idle then get the engine FULLY warm, then continue winding it out until its idling at 900rpm

if u cant get it down that far u have an airleak somewhere, but if u wind the throttlebody down u should be able to hear the leak very clearly..

once the idle is correct you should be good to go, however note that it will idle high on coldstart as the ICV channels are much larger and the fine control isnt quite right

[Aragorn]

idle stepper fault is occuring becuase the ecu has closed the ICV completely and its still idling high so it assumes a fault with ICV

map sensor fault will occur if its not piped into manifold?

[Adam]

Also swap your ICV back to the 1.8 one.
The 1.2/1.4 has a different icv, the plunger is a different shape.
Which i didn't know till yesterday.

With the 1.2/1.4 icv you will get a high idle, as the plunger end doesn't fit the hole inside the tb correctly.

[johnny27]

will do that, as for the throttle stop screw, the flap at the bottom of the tb is fully closed on idle, will adjusting it be any good for as far as i see its already fully resting?

[Adam]

Hold the tb up to the light and you will see light around the throttle plate
Closing the gap should lower the idle.