Audi A6 (AEL), cold start... idle speed fluctuates

When I start my Audi A6 (AEL, 1995) in the morning (cold start), the idle speed fluctuates between 1000 and 750 rpm and it's difficult to start (it seems like only some cylinders are starting well).

I tried with:
* double pre-heating (I'm not sure about this term in eng )
* setting timing to a slightly higher value than the standard values (using the vagcom TDI timing tool)
* accelerating a little bit during the start-up

But nothing seems to help

Could this problem be related to G80 Implausible Signal (AEL)??

Thanks, in advance.

[Translating...]

Hi Laurento,

are you sure all glow plugs are ok and heat well ?
Is the wiring of them as easy accessible as it is in other TDIs ? The 1Z allows to unplug the wire (in fact it's one metall-rubber piece) very easy by just pulling it off the glow plugs.

If the AEL allows this too, try to remove it and measure the resistance of the plug. It should be at 0.8 Ohms for a cold engine and cold plug.

After 11 years one or more plugs may be dead, which results in cold start problems and occurs not until winter.

m;

[Translating...]

dieselmartin wrote:

Hi Laurento, are you sure all glow plugs are ok and heat well ? Is the wiring of them as easy accessible as it is in other TDIs ? The 1Z allows to unplug the wire (in fact it's one metall-rubber piece) very easy by just pulling it off the glow plugs. If the AEL allows this too, try to remove it and measure the resistance of the plug. It should be at 0.8 Ohms for a cold engine and cold plug. After 11 years one or more plugs may be dead, which results in cold start problems and occurs not until winter.

Many thanks for your reply

I already checked them, but using a simple light-bulb
I'll check them tomorrow using a tester and I'll post here the inspection-result

[Translating...]

For 4 plugs the tester reports 0.8 ohm and for the remaining plug 0.7 ohm
May I make some other useful tests?