Hi all, just had to move my Grandads car, an AU2 forte 6cylinder with 120k on the clock.
Upon starting it, it dropped the revs very low (car shook and lights went dim). Im not an expert but my guess would be idle speed control motor although it was recently replaced. Any ideas would be helpful thanks guys.

First time it's been started in a while?
Does it act dfferently when it's warmed up or even just moved?
Could be a sticky isc, but it would more then likly fluctuate at idle.

It was started yesterday and did the same thing. I started it 3 times today. It's only for about 3 seconds and everything is fine.

Without being there I'd say it has either a base idle problem or a small vac leak(something along the lines) after a few seconds the cars realizing the issue and bumping up the idle speed.