Polo g40 dodgy Idle

[LeonBritton123]

Im just after suggestions and ideas as to whats causing my polo to idle so dodgy!

33% of the time it will idle just right at about 950rpm
33% of the time it will idle anywhere between 1k-2k and will drop back down to 950 or stall when i bring the clutch up slightly and the other 33% of the time it will stall or idle below 950rpm for a bit and then stall.

any ideas as to what could cause it do do this?sensors? isv? air flow meter? sticky cable?

[PeteG40]

is it worse at night  (lights, stereo on etc) as i'd be testing the alternator.

and the timing too

[LeonBritton123]

my electrician mate tested the battery on tick over and with everything electrical on and he said it was good so im guessing timing.

[alan gorst]

mine was kind of the same....my altenator etc is all spot on and it was my timming being out by half a tooth which caused it (Y)

[Fred]

On that note. If a cylinder head is skimmed to near or Maximum then that would throw out the timing as well.

I`ll guess that Vernia Pulley`s are the way forward for more than just standard not being 100% accurate.

When i had my 1Ltr MK2 Loon some years ago and did the head gasket, GSF sold thicker head gaskets for
Heads that we`re skimmed but what to do with a G especially when people are using 6N metal head gaskets
can only be the vernia pulley.

How many of you use a proper or made Camshaft Locking tool.

I did a guys Cylinder head gasket a bit back and the head was skimmed a bit past Maximum as specified
by the manual and i used my cam locking tool to find the timing belt pulling the crank to one side of its
timing mark when tensioned. Nowt i could do but time it best we could.

What we need is a enthusiast 5 Axis CNC programmer who`s already made his wealth in life
to write the program and make us some heads at cost.
Oooh! The thought of it lol.

Fred.

[PeteG40]

oem timing marks are at best shit.  With my low miler with orig head gaskets it was still 1/4 tooth out!