Auto-Choke?

[morrismen]

Can anyone tell me if the Polo GTI has some kind of auto-choke system?

I've noted that my GTI starts first time everytime (bashes head on wood ) and yet it sets itself immediately at around 850 Revs from a cold start and stays there. Is this normal?

The GTI must have some sort of air temperature sensor to get the mix of air to petrol correct in this injected engine, so therefore I would expect it to adjust the Revs accordingly when cold. The reason I ask about this is I would expect to have to clean the air sensor occasionally to keep the revs running correctly when cold or hot.

In summary, I'd expect the Revs to be slightly higher on a cold start, and then to decrease slightly to 850 Revs as it warmed...

What does everyone elses GTI do from a cold start:?:

[Del_GTi]

I've noticed this aswell, my vectra used to sit at about 1200rpm until the auto-choke went off but the polo just seems to settle down to about 860rpm instantly.

[dubpolo]

mine stays at 1200 untill i move and stop then it goes down to 850

[morrismen]

Thanks for the feedback...

I just started my GTI at night when cold and when I hadn't started it for 48 hours.

I runs at 1100 - 1200 Revs for a while, providing you don't blip the throttle or starting or there after. Otherwise, it gradually decreases the Revs automatically as the engine warms up - as you'd expect!

My theori proved then, that there must be an air temperature sensor for the mix of cold/hot air to fuel. Just not sure where it is...

[morrismen]

This cold start business is bugging me. I started my GTI this morning and it immediately went to 850 Revs. Now, standing all night you'd think it should put the Revs a little higher to 1100-1200 Revs.

So, what controls this cold start mechanism

Where is this the cold start electrical connector? Anyone know?

Is there a thermosensor somewhere, i.e. thermostat connection, that might have a loose connection or a nasty carbonised coating that causes resistance to that it stops working perhaps?

Any ideas anyone

[dubpolo]

if its starting ok, leave it!!!! if it ant broke don't fix it!!!!!!!

[morrismen]

but... if it don't make the revs high one day when it's cold and been standing all night, but it does on another day, then I think it's not working properly. Thus, I think it's a loose wire or didgy connection. See? Just want to find out where this is to check it's connectivity (or lack of).

[morrismen]

There is an electrical connector somewhere which measures air temp and then allows mixing of air to petrol for when the engine is cold.

Whatever this is, it is a known intermitent issue with VW Polo's, so I'm having mine replaced.

Will try and find out more when they deal with this.

[morrismen]

It seems that there is a thermo-sensor on the thermostat housing - these are prone to going faulty; Golf's are always in the garage for having these replaced - if it is faulty then Golf's flood when hot etc. The Polo's do the opposite and do not raise the Rev's.

Also, there is a thermo-sensor on the engine block.

These are both used to sense the temperature of the coolant/engine and adjust the Rev's, mix air of petrol accordingly

I am getting the VW Dealer to look into this before winter sets in and the engine gets REALLY cold and decides it won't run properly when real cold.

[morrismen]

Well, I had my Polo GTI diagnostically checked by the VW Dealer, and they claim there is nothing wrong with the cold start or the sensors for this, according to their checks - bet they checked it after driving it up to the computer

I guess I'll have to live with it working sometimes and not others when I cold start the car

If the cold start is still not working (Revs from 1200 downwards when starting from cold) in hard winter temps, then I'll take it up wih them again.