saintrobbo

Thanks robd and pablo_ottawa

Have already run a diagnostic test, but there was no indication that the speed sensor was faulty.

Could it be the ignition switch, as this is one of the devices, which provides a trigger voltage to the fuel pump relay and the ignition coils

Can attach a diagram of the starting and charging components, if that would help.

regards

saintrobbo

jroy500

Hi! I got the same problem today.. since one month..sometime my a4 2002 3.0 is difficult to start.. when it start, the esc light come on and the idle is not very stable.. I turn off the key, restart and its all right.. but today at my brother house, the car was not wanting to start... I saw that had no 12 volts at the fuel pump fuse.. ading 12volts and it started..
Sound for the crank speed sensor??? possibility for the fuel pump relay??

I think I will buy an obd2 scanner tomorow

thank you
Josh

pablo_ottawa

Jroy,

for you it sounds like it could be the speed sensor. Your symptoms sound almost exactly like mine.

pablo_ottawa

Hey saintrobbo,

I'm guessing at this point it's the fuel pump. I mean all things point to it soooooo. The shifty thin a out this is that it's not a cheapie part so you should do a bit more digging befor you go and spend the cash BUT, the nice thing about it is that it's not a crazy difficult part to change.

Good luck my friend

jroy500

I changed the crankshaft sensor yesterday... work good since that

thanks all