new mk3 owner with idling issues

[xAntiVenxm]

Hi all,

Finally picked up my mk3 gti
she's in need of some tlc to get her back on the road, needs mot, tax, and insurance obviously.
so i've got her as a small project as im gonna try n get her running again

I'm sure an MOT tester will point out a bunch of things needing doing, the driver's side window motor is broke, there's a couple rusty bits on doors but hopefully there won't be too much. there's a puncture hole on the backbox from a rock that flew up on the motorway but unsure if they will tell me it affects emissions,

other than that i can't see anything wrong with her except for her being unable to idle..

once we got the battery charged by jumping with my mate's bmw, she starts and runs nicely, but will not idle.. have to keep your foot on the pedal to keep her going, and if you let the throttle close completely, she sputters and dies..

I've cleaned the egr valve (i think it was that anyway haha, haynes manual is incredibly vague!) and after looking on here with it's awesomely helpful topic posts I'm going to spray the throttle body down with carb cleaner when i go see her next

Now.. if that still doesn't cure the issue of having to keep the throttle open to keep her running, what would be the next step to troubleshoot and find the issue?

Also, if anywhere on here is an engine-bay diagram of the 16v 2.0 gti identifying all the parts that'd be wonderful if someone could point that out, not familiar with what the vw parts look like!

Cheers

[Dogbot]

no egr on the abf,
but the Idle stabilisation valve is under the plastic ht lead guide, this is the normal culprit of bad idle issues, check the engine electics fuse too no.15 i think it was,

the isv is a tubular shape valve, with the ignition on there should be a quiet buzz,

i would check for vacuum leaks on the pipe from the back of the inlet fannymould to the ecu (under the scuttle panel) a leak here will cause it not to run properly & it wont idle...

[xAntiVenxm]

ahh ok then that's what i cleaned, thought it was the egr, obv was the idle stabilisation valve
it was pretty clean actually.. not much carbon residue but still gave it a clean and rubbed the inside out a bit with a cotton bud.
will check the fuses too, and yeah there is a quiet buzz when you turn the ignition on
if there's still issues after i clean the throttle body, will check the vacuum pipes on the back of the inlet mould!
this is where an engine diagram would be incredibly useful, haynes manual for this car is different to others ive got, not as many pictures and even more vague than usual lol!

[xAntiVenxm]

just spent an hour looking for an engine diagram.. google has failed me

[Dogbot]

i will make you one now....

[Dogbot]

excuse the crudeness of the tools used dont have photoshop here with me but this should get you by

[xAntiVenxm]

Hero, thanks bro

google turned up loads of the 8v models but the 16v looks completely different, at least from my point of view lol!

when i first went to see the car before buying in november, i had printed out an engine diagram but didn't realise i printed the 8v version, got there and pooped a little lol was nearly twice the size of the photo i had lol!  

[xAntiVenxm]

ROFL just noticed the air filter desc. 
my motors got a powerflow exhaust but nothing done to the intake, was trying to decide whether to get an induction kit or the drilled airbox + K&N panel filter, it seems sticking an induction kit on her is a 'no-no' in the golf world?? lol

[xAntiVenxm]

Right, an update.
Put a new battery in it, old one was shot, no change.
cleaned out the throttle with carb cleaner, improved the idling to the point that if you let the revs drop (take your foot off the throttle) you barely need to press the throttle to keep her running...
i've noticed a little press-button on the throttle body?? such that when the throttle closes, the black plastic holding the throttle cable is pushed back by the spring and clicks the button..
I'm assuming this little button tells the engine it needs to take air from somewhere else to continue running at idle?
I haven't tested my theory by opening the throttle and pressing the button manually to see what will happen as I don't know what the exact function is and i don't want to risk causing damage lol
I'm gonna plug into the car's Vag-com port soon as I get the cable through in the post.

vaccuum hoses seem to be okay, can't feel any air leaking out of em, but if i've missed something hopefully the vag program i got will tell me..

[Screech16v]

You wont feel air coming out of a leaking vaccuum pipe as it will be sucking,hence the name vaccuum best to replace the old standard ones with 3mm i.d silicone any way just to make sure.