idle mixture control screw ( k jet)?

[monkeyalan]

is it common-ish for the idle mixture control screw to go missing. my cars in the garage at the mo and he says there isn't one on my car, hence it idles like a bag-o-sh!te.

i found this post earlier.
http://www.golfgtiforum.co.uk/index.php?topic=44695.0

can you get it from VW and if so does anyone know the part number cos I just phoned my local dealer and they say you have to buy the whole fuel distributor!

thanks 

[rubjonny]

are you sure its missing, its actually an allen head bolt and its pretty damn deep in the metering head...

[monkeyalan]

seems so.

are the metering heads the same for 8v and 16v?

[rubjonny]

unfortunaltly not, the air hose is much bigger.  Well I say that, I know my MK1 8v metering head was smaller, perhaps the Mk2 8v one is bigger?  You could nick the screw out of an 8v metering head though i bet.

[monkeyalan]

i think he's a retard. 

i'm pretty sure theres a screw there.
i just got a stardrive screw driver in and there was some resistance when i turned it , now it won't start.
great.

[rubjonny]

one thing to remember is dont touch the throttle when the allen key is in the adjustment hole, otherwise you could damage the metering head.  I hope thats not whats happened

[monzablue16v]

Sounds like you found it then Alan! some mechanics can't understand not having a port to plug a pc in and tell them whats wrong. It moves a tiny amount and makes quite a difference to the fuelling so fiddle with it to get it back to working, tiny turn try it, tiny turn try it.

[monkeyalan]

i'm not sure if i tried to start it with the tool in place. 

i'll have a go tomorrow when i've calmed down a bit.

got my eye on a couple of new metering heads just in case.

how much should i pay for a good second hand one?

[monkeyalan]

if i need to change the metering head is it safe to undo the fuel lines at the head ( including supply and return) or will they be pressurised and send petrol spraying all over the shop?

i assume they will drip a bit of fuel even if not?

[rubjonny]

start the car, then pull the fuel pump relay.  this should drain most of the residual pressure from the lines, then give it an hour or so just to be sure.  Crack the lines off with a rag in hand to catch any fuel and you'll be all set