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golf3
04-02-2007, 12:50 PM
Hey!

When the engine is cold, it dies repeatedly after being started. It's annoying, but I can control it by holding the throttle open a little until it gets warm enough to control itself.

Now, as far as I can tell, the idle stabilization valve will open a little more when cold, and gets the cue from the coolant temp sensor. When warm, it will go back to normal.

Now, here's the deal...

I unplugged the signal wire to the isv, and it didn't change anything.
So i checked the voltage over the two signal wires, it read just under 1 volt when warm and idling normally.

When I get a hand, i will check the voltage to see if it changes when i try another cold start...

Therefore, can i assume there is a problem with the isv, or the ecu...given the loom is ok as there is voltage and complete circuit there...

pics for clicks..
http://img477.imageshack.us/img477/6958/mk316vgl2.jpg

h100vw
04-02-2007, 01:02 PM
Clean out the throttlebody really well with some carb cleaner and a rag. I'd also have a look at it with VAG-COM there maybe a problem somewhere else.

Other things that come to mind are the water temp sensor that feeds the computer could ba giving out a duff value causing the computer to lose control.

Does this only happen after being stood over night?

With VAG-COM you can check that the throttle pot is changing smoothly from closed to full throttle.

GAvin

Bora Sport
10-02-2007, 08:26 AM
Can you feel it vibrating? It should be buzzing or vibrating when it is working.